551961531 has 12 divisors (see below), whose sum is σ = 869757720. Its totient is φ = 334522080.

The previous prime is 551961511. The next prime is 551961563. The reversal of 551961531 is 135169155.

551961531 is a `hidden beast` number, since 5 + 5 + 1 + 9 + 615 + 31 = 666.

551961531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 551961531 - 2¹⁵ = 551928763 is a prime.

It is a super-2 number, since 2×551961531² = 609323063407727922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (551961511) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2787586 + ... + 2787783.

It is an arithmetic number, because the mean of its divisors is an integer number (72479810).

Almost surely, 2^551961531 is an apocalyptic number.

551961531 is a deficient number, since it is larger than the sum of its proper divisors (317796189).

551961531 is a wasteful number, since it uses less digits than its factorization.

551961531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5575386 (or 5575383 counting only the distinct ones).

The product of its digits is 20250, while the sum is 36.

The square root of 551961531 is about 23493.8615599905. The cubic root of 551961531 is about 820.2941295630.

The spelling of 551961531 in words is "five hundred fifty-one million, nine hundred sixty-one thousand, five hundred thirty-one".