64400651 has 16 divisors (see below), whose sum is σ = 75456000. Its totient is φ = 54941544.

The previous prime is 64400617. The next prime is 64400659. The reversal of 64400651 is 15600446.

It is a happy number.

It is not a de Polignac number, because 64400651 - 2⁶ = 64400587 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64400651.

It is not an unprimeable number, because it can be changed into a prime (64400659) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 122876 + ... + 123398.

It is an arithmetic number, because the mean of its divisors is an integer number (4716000).

Almost surely, 2^64400651 is an apocalyptic number.

64400651 is a deficient number, since it is larger than the sum of its proper divisors (11055349).

64400651 is an equidigital number, since it uses as much as digits as its factorization.

64400651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 903 (or 889 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 64400651 is about 8025.0016199375. The cubic root of 64400651 is about 400.8329538491.

Subtracting from 64400651 its sum of digits (26), we obtain a square (64400625 = 8025²).

The spelling of 64400651 in words is "sixty-four million, four hundred thousand, six hundred fifty-one".