251160561 has 16 divisors (see below), whose sum is σ = 384921600. Its totient is φ = 161666064.

The previous prime is 251160541. The next prime is 251160577. The reversal of 251160561 is 165061152.

It is a happy number.

251160561 is a `hidden beast` number, since 2 + 51 + 1 + 605 + 6 + 1 = 666.

It is not a de Polignac number, because 251160561 - 2¹¹ = 251158513 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (251160541) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 159601 + ... + 161166.

It is an arithmetic number, because the mean of its divisors is an integer number (24057600).

Almost surely, 2^251160561 is an apocalyptic number.

It is an amenable number.

251160561 is a deficient number, since it is larger than the sum of its proper divisors (133761039).

251160561 is a wasteful number, since it uses less digits than its factorization.

251160561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320805 (or 320799 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 27.

The square root of 251160561 is about 15848.0459678788. The cubic root of 251160561 is about 630.9338305459.

The spelling of 251160561 in words is "two hundred fifty-one million, one hundred sixty thousand, five hundred sixty-one".