64251840 has 224 divisors, whose sum is σ = 224722944. Its totient is φ = 15482880.

The previous prime is 64251833. The next prime is 64251851. The reversal of 64251840 is 4815246.

64251840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 64251798 and 64251807.

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 31 ways as a sum of consecutive naturals, for example, 505857 + ... + 505983.

Almost surely, 2^64251840 is an apocalyptic number.

64251840 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 64251840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112361472).

64251840 is an abundant number, since it is smaller than the sum of its proper divisors (160471104).

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

64251840 is a wasteful number, since it uses less digits than its factorization.

64251840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195 (or 185 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 30.

The square root of 64251840 is about 8015.7245461655. The cubic root of 64251840 is about 400.5239799794.

The spelling of 64251840 in words is "sixty-four million, two hundred fifty-one thousand, eight hundred forty".