64765440 has 160 divisors (see below), whose sum is σ = 230297760. Its totient is φ = 17252352.

The previous prime is 64765423. The next prime is 64765451. The reversal of 64765440 is 4456746.

64765440 is a `hidden beast` number, since 647 + 6 + 5 + 4 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (160).

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 = 64765395 and 64765404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68652 + ... + 69588.

It is an arithmetic number, because the mean of its divisors is an integer number (1439361).

Almost surely, 2^64765440 is an apocalyptic number.

64765440 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 64765440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115148880).

64765440 is an abundant number, since it is smaller than the sum of its proper divisors (165532320).

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

64765440 is an equidigital number, since it uses as much as digits as its factorization.

64765440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 969 (or 947 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 36.

The square root of 64765440 is about 8047.6978074478. The cubic root of 64765440 is about 401.5883511698.

The spelling of 64765440 in words is "sixty-four million, seven hundred sixty-five thousand, four hundred forty".