257421133 has 2 divisors, whose sum is σ = 257421134. Its totient is φ = 257421132.

The previous prime is 257421127. The next prime is 257421163. The reversal of 257421133 is 331124752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 198161929 + 59259204 = 14077^2 + 7698^2 .

It is a cyclic number.

It is not a de Polignac number, because 257421133 - 2²⁵ = 223866701 is a prime.

It is equal to p_14062771 and since 257421133 and 14062771 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257421163) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128710566 + 128710567.

It is an arithmetic number, because the mean of its divisors is an integer number (128710567).

Almost surely, 2^257421133 is an apocalyptic number.

It is an amenable number.

257421133 is a deficient number, since it is larger than the sum of its proper divisors (1).

257421133 is an equidigital number, since it uses as much as digits as its factorization.

257421133 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5040, while the sum is 28.

The square root of 257421133 is about 16044.3489428521. The cubic root of 257421133 is about 636.1332053903.

Adding to 257421133 its reverse (331124752), we get a palindrome (588545885).

The spelling of 257421133 in words is "two hundred fifty-seven million, four hundred twenty-one thousand, one hundred thirty-three".