257661761 has 8 divisors (see below), whose sum is σ = 296278464. Its totient is φ = 219497040.

The previous prime is 257661731. The next prime is 257661763. The reversal of 257661761 is 167166752.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 257661761 - 2²⁶ = 190552897 is a prime.

It is a super-2 number, since 2×257661761² = 132779166163242242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257661763) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111770 + ... + 114051.

It is an arithmetic number, because the mean of its divisors is an integer number (37034808).

Almost surely, 2^257661761 is an apocalyptic number.

It is an amenable number.

257661761 is a deficient number, since it is larger than the sum of its proper divisors (38616703).

257661761 is a wasteful number, since it uses less digits than its factorization.

257661761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225991.

The product of its digits is 105840, while the sum is 41.

The square root of 257661761 is about 16051.8460309087. The cubic root of 257661761 is about 636.3313551287.

The spelling of 257661761 in words is "two hundred fifty-seven million, six hundred sixty-one thousand, seven hundred sixty-one".