64659902921 has 8 divisors (see below), whose sum is σ = 67733743104. Its totient is φ = 61607941120.

The previous prime is 64659902899. The next prime is 64659902927. The reversal of 64659902921 is 12920995646.

It is a happy number.

64659902921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64659902921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64659902927) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5463545 + ... + 5475366.

It is an arithmetic number, because the mean of its divisors is an integer number (8466717888).

Almost surely, 2^64659902921 is an apocalyptic number.

It is an amenable number.

64659902921 is a deficient number, since it is larger than the sum of its proper divisors (3073840183).

64659902921 is a wasteful number, since it uses less digits than its factorization.

64659902921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10939191.

The product of its (nonzero) digits is 2099520, while the sum is 53.

The spelling of 64659902921 in words is "sixty-four billion, six hundred fifty-nine million, nine hundred two thousand, nine hundred twenty-one".