2564666556 has 12 divisors (see below), whose sum is σ = 5984221992. Its totient is φ = 854888848.

The previous prime is 2564666519. The next prime is 2564666567. The reversal of 2564666556 is 6556664652.

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

It is a super-2 number, since 2×2564666556² = 13155029086929802272, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2564666499 and 2564666508.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106861095 + ... + 106861118.

It is an arithmetic number, because the mean of its divisors is an integer number (498685166).

Almost surely, 2^2564666556 is an apocalyptic number.

It is an amenable number.

2564666556 is an abundant number, since it is smaller than the sum of its proper divisors (3419555436).

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

2564666556 is a wasteful number, since it uses less digits than its factorization.

2564666556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213722220 (or 213722218 counting only the distinct ones).

The product of its digits is 7776000, while the sum is 51.

The square root of 2564666556 is about 50642.5370217567. The cubic root of 2564666556 is about 1368.8114713786.

The spelling of 2564666556 in words is "two billion, five hundred sixty-four million, six hundred sixty-six thousand, five hundred fifty-six".