56161531 has 2 divisors, whose sum is σ = 56161532. Its totient is φ = 56161530.

The previous prime is 56161519. The next prime is 56161537. The reversal of 56161531 is 13516165.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 56161531 - 2⁵ = 56161499 is a prime.

It is a super-2 number, since 2×56161531² = 6308235128527922, which contains 22 as substring.

It is equal to p_3347452 and since 56161531 and 3347452 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 56161531.

It is not a weakly prime, because it can be changed into another prime (56161537) 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, 28080765 + 28080766.

It is an arithmetic number, because the mean of its divisors is an integer number (28080766).

Almost surely, 2^56161531 is an apocalyptic number.

56161531 is a deficient number, since it is larger than the sum of its proper divisors (1).

56161531 is an equidigital number, since it uses as much as digits as its factorization.

56161531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2700, while the sum is 28.

The square root of 56161531 is about 7494.0997458000. The cubic root of 56161531 is about 382.9537378195.

Adding to 56161531 its reverse (13516165), we get a palindrome (69677696).

The spelling of 56161531 in words is "fifty-six million, one hundred sixty-one thousand, five hundred thirty-one".