1656686604 has 12 divisors (see below), whose sum is σ = 3865602104. Its totient is φ = 552228864.

The previous prime is 1656686569. The next prime is 1656686609. The reversal of 1656686604 is 4066866561.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×1656686604² = 5489221007746105632, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1656686609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69028597 + ... + 69028620.

Almost surely, 2^1656686604 is an apocalyptic number.

It is an amenable number.

1656686604 is an abundant number, since it is smaller than the sum of its proper divisors (2208915500).

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

1656686604 is a wasteful number, since it uses less digits than its factorization.

1656686604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138057224 (or 138057222 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 48.

The square root of 1656686604 is about 40702.4152108938. The cubic root of 1656686604 is about 1183.2598275485.

The spelling of 1656686604 in words is "one billion, six hundred fifty-six million, six hundred eighty-six thousand, six hundred four".