56947721 has 2 divisors, whose sum is σ = 56947722. Its totient is φ = 56947720.

The previous prime is 56947697. The next prime is 56947753. The reversal of 56947721 is 12774965.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 52765696 + 4182025 = 7264^2 + 2045^2 .

It is a cyclic number.

It is not a de Polignac number, because 56947721 - 2¹⁰ = 56946697 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (56947771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28473860 + 28473861.

It is an arithmetic number, because the mean of its divisors is an integer number (28473861).

Almost surely, 2^56947721 is an apocalyptic number.

It is an amenable number.

56947721 is a deficient number, since it is larger than the sum of its proper divisors (1).

56947721 is an equidigital number, since it uses as much as digits as its factorization.

56947721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 105840, while the sum is 41.

The square root of 56947721 is about 7546.3713796765. The cubic root of 56947721 is about 384.7324187811.

The spelling of 56947721 in words is "fifty-six million, nine hundred forty-seven thousand, seven hundred twenty-one".