56519821 has 2 divisors, whose sum is σ = 56519822. Its totient is φ = 56519820.

The previous prime is 56519791. The next prime is 56519833. The reversal of 56519821 is 12891565.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49702500 + 6817321 = 7050^2 + 2611^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-56519821 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56519921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28259910 + 28259911.

It is an arithmetic number, because the mean of its divisors is an integer number (28259911).

Almost surely, 2^56519821 is an apocalyptic number.

56519821 is the 4341-st hex number.

It is an amenable number.

56519821 is a deficient number, since it is larger than the sum of its proper divisors (1).

56519821 is an equidigital number, since it uses as much as digits as its factorization.

56519821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21600, while the sum is 37.

The square root of 56519821 is about 7517.9665468795. The cubic root of 56519821 is about 383.7663803411.

The spelling of 56519821 in words is "fifty-six million, five hundred nineteen thousand, eight hundred twenty-one".