251315 has 4 divisors (see below), whose sum is σ = 301584. Its totient is φ = 201048.

The previous prime is 251297. The next prime is 251323. The reversal of 251315 is 513152.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 251315 - 2⁸ = 251059 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 251293 and 251302.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 251315.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25127 + ... + 25136.

It is an arithmetic number, because the mean of its divisors is an integer number (75396).

2²⁵¹³¹⁵ is an apocalyptic number.

251315 is a deficient number, since it is larger than the sum of its proper divisors (50269).

251315 is an equidigital number, since it uses as much as digits as its factorization.

251315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50268.

The product of its digits is 150, while the sum is 17.

The square root of 251315 is about 501.3132753080. The cubic root of 251315 is about 63.1063124763.

Adding to 251315 its reverse (513152), we get a palindrome (764467).

The spelling of 251315 in words is "two hundred fifty-one thousand, three hundred fifteen".