556391161 has 4 divisors (see below), whose sum is σ = 556548772. Its totient is φ = 556233552.

The previous prime is 556391159. The next prime is 556391167. The reversal of 556391161 is 161193655.

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

It can be written as a sum of positive squares in 2 ways, for example, as 154629225 + 401761936 = 12435^2 + 20044^2 .

It is a cyclic number.

It is not a de Polignac number, because 556391161 - 2¹ = 556391159 is a prime.

It is a super-2 number, since 2×556391161² = 619142248077855842, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 556391161.

It is not an unprimeable number, because it can be changed into a prime (556391167) 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, 73386 + ... + 80611.

It is an arithmetic number, because the mean of its divisors is an integer number (139137193).

Almost surely, 2^556391161 is an apocalyptic number.

It is an amenable number.

556391161 is a deficient number, since it is larger than the sum of its proper divisors (157611).

556391161 is a wasteful number, since it uses less digits than its factorization.

556391161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157610.

The product of its digits is 24300, while the sum is 37.

The square root of 556391161 is about 23587.9452475200. The cubic root of 556391161 is about 822.4826410234.

The spelling of 556391161 in words is "five hundred fifty-six million, three hundred ninety-one thousand, one hundred sixty-one".