257135561 has 8 divisors (see below), whose sum is σ = 268484544. Its totient is φ = 245800720.

The previous prime is 257135551. The next prime is 257135563. The reversal of 257135561 is 165531752.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257135561 is a prime.

It is a super-2 number, since 2×257135561² = 132237393461569442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257135563) 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, 53135 + ... + 57771.

It is an arithmetic number, because the mean of its divisors is an integer number (33560568).

Almost surely, 2^257135561 is an apocalyptic number.

It is an amenable number.

257135561 is a deficient number, since it is larger than the sum of its proper divisors (11348983).

257135561 is a wasteful number, since it uses less digits than its factorization.

257135561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7071.

The product of its digits is 31500, while the sum is 35.

The square root of 257135561 is about 16035.4470159082. The cubic root of 257135561 is about 635.8978853566.

The spelling of 257135561 in words is "two hundred fifty-seven million, one hundred thirty-five thousand, five hundred sixty-one".