251161403 has 16 divisors (see below), whose sum is σ = 267321600. Its totient is φ = 235486944.

The previous prime is 251161387. The next prime is 251161429. The reversal of 251161403 is 304161152.

It is a cyclic number.

It is not a de Polignac number, because 251161403 - 2⁴ = 251161387 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (251161003) 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, 284000 + ... + 284882.

It is an arithmetic number, because the mean of its divisors is an integer number (16707600).

Almost surely, 2^251161403 is an apocalyptic number.

251161403 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

251161403 is a deficient number, since it is larger than the sum of its proper divisors (16160197).

251161403 is a wasteful number, since it uses less digits than its factorization.

251161403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1138.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 251161403 is about 15848.0725326457. The cubic root of 251161403 is about 630.9345356005.

The spelling of 251161403 in words is "two hundred fifty-one million, one hundred sixty-one thousand, four hundred three".