257406261 has 12 divisors (see below), whose sum is σ = 399242592. Its totient is φ = 147089208.

The previous prime is 257406217. The next prime is 257406269. The reversal of 257406261 is 162604752.

It is not a de Polignac number, because 257406261 - 2¹⁰ = 257405237 is a prime.

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257406269) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 875385 + ... + 875678.

It is an arithmetic number, because the mean of its divisors is an integer number (33270216).

Almost surely, 2^257406261 is an apocalyptic number.

257406261 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

257406261 is a deficient number, since it is larger than the sum of its proper divisors (141836331).

257406261 is a wasteful number, since it uses less digits than its factorization.

257406261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1751080 (or 1751073 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 33.

The square root of 257406261 is about 16043.8854707954. The cubic root of 257406261 is about 636.1209547059.

The spelling of 257406261 in words is "two hundred fifty-seven million, four hundred six thousand, two hundred sixty-one".