64707840 has 216 divisors, whose sum is σ = 231016968. Its totient is φ = 16711680.

The previous prime is 64707833. The next prime is 64707871. The reversal of 64707840 is 4870746.

It is a happy number.

64707840 is a `hidden beast` number, since 647 + 0 + 7 + 8 + 4 + 0 = 666.

64707840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 451584 + 64256256 = 672^2 + 8016^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 64707795 and 64707804.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 472252 + ... + 472388.

It is an arithmetic number, because the mean of its divisors is an integer number (1069523).

Almost surely, 2^64707840 is an apocalyptic number.

64707840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64707840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115508484).

64707840 is an abundant number, since it is smaller than the sum of its proper divisors (166309128).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64707840 is a wasteful number, since it uses less digits than its factorization.

64707840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205 (or 188 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

The square root of 64707840 is about 8044.1183482095. The cubic root of 64707840 is about 401.4692632228.

It can be divided in two parts, 6 and 4707840, that added together give a triangular number (4707846 = T₃₀₆₈).

The spelling of 64707840 in words is "sixty-four million, seven hundred seven thousand, eight hundred forty".