57251021 has 2 divisors, whose sum is σ = 57251022. Its totient is φ = 57251020.

The previous prime is 57251011. The next prime is 57251027. The reversal of 57251021 is 12015275.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43375396 + 13875625 = 6586^2 + 3725^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-57251021 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (57251027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28625510 + 28625511.

It is an arithmetic number, because the mean of its divisors is an integer number (28625511).

Almost surely, 2^57251021 is an apocalyptic number.

It is an amenable number.

57251021 is a deficient number, since it is larger than the sum of its proper divisors (1).

57251021 is an equidigital number, since it uses as much as digits as its factorization.

57251021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 700, while the sum is 23.

The square root of 57251021 is about 7566.4404444891. The cubic root of 57251021 is about 385.4142300477.

Adding to 57251021 its reverse (12015275), we get a palindrome (69266296).

The spelling of 57251021 in words is "fifty-seven million, two hundred fifty-one thousand, twenty-one".