56751209 has 2 divisors, whose sum is σ = 56751210. Its totient is φ = 56751208.

The previous prime is 56751203. The next prime is 56751217. The reversal of 56751209 is 90215765.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38875225 + 17875984 = 6235^2 + 4228^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-56751209 is a prime.

It is not a weakly prime, because it can be changed into another prime (56751203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28375604 + 28375605.

It is an arithmetic number, because the mean of its divisors is an integer number (28375605).

Almost surely, 2^56751209 is an apocalyptic number.

It is an amenable number.

56751209 is a deficient number, since it is larger than the sum of its proper divisors (1).

56751209 is an equidigital number, since it uses as much as digits as its factorization.

56751209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18900, while the sum is 35.

The square root of 56751209 is about 7533.3398303807. The cubic root of 56751209 is about 384.2893710945.

The spelling of 56751209 in words is "fifty-six million, seven hundred fifty-one thousand, two hundred nine".