556616651581 has 2 divisors, whose sum is σ = 556616651582. Its totient is φ = 556616651580.

The previous prime is 556616651573. The next prime is 556616651597. The reversal of 556616651581 is 185156616655.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 476008924356 + 80607727225 = 689934^2 + 283915^2 .

It is a cyclic number.

It is not a de Polignac number, because 556616651581 - 2³ = 556616651573 is a prime.

It is a super-2 number, since 2×556616651581² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (556616651551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 278308325790 + 278308325791.

It is an arithmetic number, because the mean of its divisors is an integer number (278308325791).

Almost surely, 2^556616651581 is an apocalyptic number.

It is an amenable number.

556616651581 is a deficient number, since it is larger than the sum of its proper divisors (1).

556616651581 is an equidigital number, since it uses as much as digits as its factorization.

556616651581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480000, while the sum is 55.

The spelling of 556616651581 in words is "five hundred fifty-six billion, six hundred sixteen million, six hundred fifty-one thousand, five hundred eighty-one".