57942809 has 2 divisors, whose sum is σ = 57942810. Its totient is φ = 57942808.

The previous prime is 57942803. The next prime is 57942877. The reversal of 57942809 is 90824975.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34633225 + 23309584 = 5885^2 + 4828^2 .

It is a cyclic number.

It is not a de Polignac number, because 57942809 - 2⁴ = 57942793 is a prime.

It is a super-2 number, since 2×57942809² = 6714738229620962, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 57942809.

It is not a weakly prime, because it can be changed into another prime (57942803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28971404 + 28971405.

It is an arithmetic number, because the mean of its divisors is an integer number (28971405).

Almost surely, 2^57942809 is an apocalyptic number.

It is an amenable number.

57942809 is a deficient number, since it is larger than the sum of its proper divisors (1).

57942809 is an equidigital number, since it uses as much as digits as its factorization.

57942809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 44.

The square root of 57942809 is about 7612.0174067063. The cubic root of 57942809 is about 386.9603927354.

The spelling of 57942809 in words is "fifty-seven million, nine hundred forty-two thousand, eight hundred nine".