257563091 has 2 divisors, whose sum is σ = 257563092. Its totient is φ = 257563090.

The previous prime is 257563081. The next prime is 257563127. The reversal of 257563091 is 190365752.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257563091 is a prime.

It is not a weakly prime, because it can be changed into another prime (257563021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128781545 + 128781546.

It is an arithmetic number, because the mean of its divisors is an integer number (128781546).

Almost surely, 2^257563091 is an apocalyptic number.

257563091 is a deficient number, since it is larger than the sum of its proper divisors (1).

257563091 is an equidigital number, since it uses as much as digits as its factorization.

257563091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56700, while the sum is 38.

The square root of 257563091 is about 16048.7722583380. The cubic root of 257563091 is about 636.2501183542.

It can be divided in two parts, 2575 and 63091, that multiplied together give a triangular number (162459325 = T₁₈₀₂₅).

The spelling of 257563091 in words is "two hundred fifty-seven million, five hundred sixty-three thousand, ninety-one".