56861551 has 2 divisors, whose sum is σ = 56861552. Its totient is φ = 56861550.

The previous prime is 56861531. The next prime is 56861569. The reversal of 56861551 is 15516865.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 56861551 - 2⁷ = 56861423 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 56861551.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56861521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28430775 + 28430776.

It is an arithmetic number, because the mean of its divisors is an integer number (28430776).

Almost surely, 2^56861551 is an apocalyptic number.

56861551 is a deficient number, since it is larger than the sum of its proper divisors (1).

56861551 is an equidigital number, since it uses as much as digits as its factorization.

56861551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36000, while the sum is 37.

The square root of 56861551 is about 7540.6598517636. The cubic root of 56861551 is about 384.5382692030.

The spelling of 56861551 in words is "fifty-six million, eight hundred sixty-one thousand, five hundred fifty-one".