257672729 has 2 divisors, whose sum is σ = 257672730. Its totient is φ = 257672728.

The previous prime is 257672719. The next prime is 257672747. The reversal of 257672729 is 927276752.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 171610000 + 86062729 = 13100^2 + 9277^2 .

It is a cyclic number.

It is not a de Polignac number, because 257672729 - 2¹⁶ = 257607193 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (257672719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128836364 + 128836365.

It is an arithmetic number, because the mean of its divisors is an integer number (128836365).

Almost surely, 2^257672729 is an apocalyptic number.

It is an amenable number.

257672729 is a deficient number, since it is larger than the sum of its proper divisors (1).

257672729 is an equidigital number, since it uses as much as digits as its factorization.

257672729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 740880, while the sum is 47.

The square root of 257672729 is about 16052.1876702212. The cubic root of 257672729 is about 636.3403839982.

The spelling of 257672729 in words is "two hundred fifty-seven million, six hundred seventy-two thousand, seven hundred twenty-nine".