251289 has 16 divisors (see below), whose sum is σ = 383040. Its totient is φ = 162720.

The previous prime is 251287. The next prime is 251291. The reversal of 251289 is 982152.

It is an interprime number because it is at equal distance from previous prime (251287) and next prime (251291).

It is not a de Polignac number, because 251289 - 2¹ = 251287 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 994 + ... + 1220.

It is an arithmetic number, because the mean of its divisors is an integer number (23940).

2²⁵¹²⁸⁹ is an apocalyptic number.

It is an amenable number.

251289 is a deficient number, since it is larger than the sum of its proper divisors (131751).

251289 is a wasteful number, since it uses less digits than its factorization.

251289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277 (or 271 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 251289 is about 501.2873427486. The cubic root of 251289 is about 63.1041361628.

It can be divided in two parts, 2512 and 89, that added together give a square (2601 = 51²).

The spelling of 251289 in words is "two hundred fifty-one thousand, two hundred eighty-nine".