56281531 has 2 divisors, whose sum is σ = 56281532. Its totient is φ = 56281530.

The previous prime is 56281481. The next prime is 56281549. The reversal of 56281531 is 13518265.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 56281531 - 2¹⁷ = 56150459 is a prime.

It is a super-2 number, since 2×56281531² = 6335221463407922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 56281493 and 56281502.

It is not a weakly prime, because it can be changed into another prime (56281031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28140765 + 28140766.

It is an arithmetic number, because the mean of its divisors is an integer number (28140766).

Almost surely, 2^56281531 is an apocalyptic number.

56281531 is a deficient number, since it is larger than the sum of its proper divisors (1).

56281531 is an equidigital number, since it uses as much as digits as its factorization.

56281531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7200, while the sum is 31.

The square root of 56281531 is about 7502.1017721702. The cubic root of 56281531 is about 383.2262954245.

Adding to 56281531 its reverse (13518265), we get a palindrome (69799796).

The spelling of 56281531 in words is "fifty-six million, two hundred eighty-one thousand, five hundred thirty-one".