56561389 has 2 divisors, whose sum is σ = 56561390. Its totient is φ = 56561388.

The previous prime is 56561381. The next prime is 56561399. The reversal of 56561389 is 98316565.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 53728900 + 2832489 = 7330^2 + 1683^2 .

It is a cyclic number.

It is not a de Polignac number, because 56561389 - 2³ = 56561381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56561381) 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, 28280694 + 28280695.

It is an arithmetic number, because the mean of its divisors is an integer number (28280695).

Almost surely, 2^56561389 is an apocalyptic number.

It is an amenable number.

56561389 is a deficient number, since it is larger than the sum of its proper divisors (1).

56561389 is an equidigital number, since it uses as much as digits as its factorization.

56561389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 194400, while the sum is 43.

The square root of 56561389 is about 7520.7306161037. The cubic root of 56561389 is about 383.8604387406.

The spelling of 56561389 in words is "fifty-six million, five hundred sixty-one thousand, three hundred eighty-nine".