257345906 has 4 divisors (see below), whose sum is σ = 386018862. Its totient is φ = 128672952.

The previous prime is 257345863. The next prime is 257345917. The reversal of 257345906 is 609543752.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 174372025 + 82973881 = 13205^2 + 9109^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64336475 + ... + 64336478.

Almost surely, 2^257345906 is an apocalyptic number.

257345906 is a deficient number, since it is larger than the sum of its proper divisors (128672956).

257345906 is a wasteful number, since it uses less digits than its factorization.

257345906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128672955.

The product of its (nonzero) digits is 226800, while the sum is 41.

The square root of 257345906 is about 16042.0044258814. The cubic root of 257345906 is about 636.0712329402.

The spelling of 257345906 in words is "two hundred fifty-seven million, three hundred forty-five thousand, nine hundred six".