556607015721 has 27 divisors (see below), whose sum is σ = 807256695063. Its totient is φ = 369568776960.

The previous prime is 556607015707. The next prime is 556607015863. The reversal of 556607015721 is 127510706655.

The square root of 556607015721 is 746061.

It is a perfect power (a square), and thus also a powerful number.

556607015721 is a `hidden beast` number, since 5 + 5 + 6 + 6 + 0 + 70 + 1 + 572 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 552755075625 + 3851940096 = 743475^2 + 62064^2 .

It is not a de Polignac number, because 556607015721 - 2⁷ = 556607015593 is a prime.

It is a super-2 number, since 2×556607015721² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (556607011721) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 964656585 + ... + 964657161.

Almost surely, 2^556607015721 is an apocalyptic number.

556607015721 is the 746061-st square number.

556607015721 is the 373031-st centered octagonal number.

It is an amenable number.

556607015721 is a deficient number, since it is larger than the sum of its proper divisors (250649679342).

556607015721 is an frugal number, since it uses more digits than its factorization.

556607015721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2022 (or 1011 counting only the distinct ones).

The product of its (nonzero) digits is 441000, while the sum is 45.

The spelling of 556607015721 in words is "five hundred fifty-six billion, six hundred seven million, fifteen thousand, seven hundred twenty-one".