656009165251 has 4 divisors (see below), whose sum is σ = 715646362104. Its totient is φ = 596371968400.

The previous prime is 656009165221. The next prime is 656009165269. The reversal of 656009165251 is 152561900656.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-656009165251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (656009165221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29818598410 + ... + 29818598431.

It is an arithmetic number, because the mean of its divisors is an integer number (178911590526).

Almost surely, 2^656009165251 is an apocalyptic number.

656009165251 is a deficient number, since it is larger than the sum of its proper divisors (59637196853).

656009165251 is a wasteful number, since it uses less digits than its factorization.

656009165251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59637196852.

The product of its (nonzero) digits is 486000, while the sum is 46.

The spelling of 656009165251 in words is "six hundred fifty-six billion, nine million, one hundred sixty-five thousand, two hundred fifty-one".