251089 has 4 divisors (see below), whose sum is σ = 252324. Its totient is φ = 249856.

The previous prime is 251087. The next prime is 251099. The reversal of 251089 is 980152.

251089 is nontrivially palindromic in base 15.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 242064 + 9025 = 492^2 + 95^2 .

It is a cyclic number.

It is not a de Polignac number, because 251089 - 2¹ = 251087 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (251081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 232 + ... + 745.

It is an arithmetic number, because the mean of its divisors is an integer number (63081).

2²⁵¹⁰⁸⁹ is an apocalyptic number.

It is an amenable number.

251089 is a deficient number, since it is larger than the sum of its proper divisors (1235).

251089 is an equidigital number, since it uses as much as digits as its factorization.

251089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1234.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 251089 is about 501.0878166549. The cubic root of 251089 is about 63.0873902686.

It can be divided in two parts, 25 and 1089, that multiplied together give a square (27225 = 165²).

The spelling of 251089 in words is "two hundred fifty-one thousand, eighty-nine".