64640640156 has 24 divisors (see below), whose sum is σ = 150867052560. Its totient is φ = 21541324032.

The previous prime is 64640640137. The next prime is 64640640199. The reversal of 64640640156 is 65104604646.

64640640156 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 645891 + ... + 739226.

It is an arithmetic number, because the mean of its divisors is an integer number (6286127190).

Almost surely, 2^64640640156 is an apocalyptic number.

It is an amenable number.

64640640156 is an abundant number, since it is smaller than the sum of its proper divisors (86226412404).

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

64640640156 is a wasteful number, since it uses less digits than its factorization.

64640640156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1389013 (or 1389011 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 42.

The spelling of 64640640156 in words is "sixty-four billion, six hundred forty million, six hundred forty thousand, one hundred fifty-six".