57191389 has 2 divisors, whose sum is σ = 57191390. Its totient is φ = 57191388.

The previous prime is 57191377. The next prime is 57191413. The reversal of 57191389 is 98319175.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50168889 + 7022500 = 7083^2 + 2650^2 .

It is a cyclic number.

It is not a de Polignac number, because 57191389 - 2⁵ = 57191357 is a prime.

It is a plaindrome in base 16.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (57191369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28595694 + 28595695.

It is an arithmetic number, because the mean of its divisors is an integer number (28595695).

Almost surely, 2^57191389 is an apocalyptic number.

It is an amenable number.

57191389 is a deficient number, since it is larger than the sum of its proper divisors (1).

57191389 is an equidigital number, since it uses as much as digits as its factorization.

57191389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 68040, while the sum is 43.

The square root of 57191389 is about 7562.4988595040. The cubic root of 57191389 is about 385.2803692292.

The spelling of 57191389 in words is "fifty-seven million, one hundred ninety-one thousand, three hundred eighty-nine".