655666556 has 12 divisors (see below), whose sum is σ = 1164542568. Its totient is φ = 322940112.

The previous prime is 655666511. The next prime is 655666559.

It is a happy number.

655666556 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×655666556² = 859797265313802272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655666559) 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, 1222991 + ... + 1223526.

It is an arithmetic number, because the mean of its divisors is an integer number (97045214).

Almost surely, 2^655666556 is an apocalyptic number.

It is an amenable number.

655666556 is a deficient number, since it is larger than the sum of its proper divisors (508876012).

655666556 is a wasteful number, since it uses less digits than its factorization.

655666556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2446588 (or 2446586 counting only the distinct ones).

The product of its digits is 4860000, while the sum is 50.

The square root of 655666556 is about 25605.9867218586. The cubic root of 655666556 is about 868.7490525601.

The spelling of 655666556 in words is "six hundred fifty-five million, six hundred sixty-six thousand, five hundred fifty-six".