57139661 has 2 divisors, whose sum is σ = 57139662. Its totient is φ = 57139660.

The previous prime is 57139637. The next prime is 57139697. The reversal of 57139661 is 16693175.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43494025 + 13645636 = 6595^2 + 3694^2 .

It is a cyclic number.

It is not a de Polignac number, because 57139661 - 2⁶ = 57139597 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 (57139961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28569830 + 28569831.

It is an arithmetic number, because the mean of its divisors is an integer number (28569831).

Almost surely, 2^57139661 is an apocalyptic number.

It is an amenable number.

57139661 is a deficient number, since it is larger than the sum of its proper divisors (1).

57139661 is an equidigital number, since it uses as much as digits as its factorization.

57139661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34020, while the sum is 38.

The square root of 57139661 is about 7559.0780522495. The cubic root of 57139661 is about 385.1641757780.

The spelling of 57139661 in words is "fifty-seven million, one hundred thirty-nine thousand, six hundred sixty-one".