56783921 has 2 divisors, whose sum is σ = 56783922. Its totient is φ = 56783920.

The previous prime is 56783899. The next prime is 56783929. The reversal of 56783921 is 12938765.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40462321 + 16321600 = 6361^2 + 4040^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-56783921 is a prime.

It is not a weakly prime, because it can be changed into another prime (56783929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28391960 + 28391961.

It is an arithmetic number, because the mean of its divisors is an integer number (28391961).

Almost surely, 2^56783921 is an apocalyptic number.

It is an amenable number.

56783921 is a deficient number, since it is larger than the sum of its proper divisors (1).

56783921 is an equidigital number, since it uses as much as digits as its factorization.

56783921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 41.

The square root of 56783921 is about 7535.5106661725. The cubic root of 56783921 is about 384.3631930716.

The spelling of 56783921 in words is "fifty-six million, seven hundred eighty-three thousand, nine hundred twenty-one".