251487 has 6 divisors (see below), whose sum is σ = 363272. Its totient is φ = 167652.

The previous prime is 251483. The next prime is 251491. The reversal of 251487 is 784152.

251487 is nontrivially palindromic in base 4.

It is an interprime number because it is at equal distance from previous prime (251483) and next prime (251491).

It is not a de Polignac number, because 251487 - 2² = 251483 is a prime.

It is a super-2 number, since 2×251487² = 126491422338, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 251487.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 251487.

It is not an unprimeable number, because it can be changed into a prime (251483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13963 + ... + 13980.

2²⁵¹⁴⁸⁷ is an apocalyptic number.

251487 is a deficient number, since it is larger than the sum of its proper divisors (111785).

251487 is a wasteful number, since it uses less digits than its factorization.

251487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27949 (or 27946 counting only the distinct ones).

The product of its digits is 2240, while the sum is 27.

The square root of 251487 is about 501.4847953827. The cubic root of 251487 is about 63.1207058478.

It can be divided in two parts, 2514 and 87, that added together give a square (2601 = 51²).

The spelling of 251487 in words is "two hundred fifty-one thousand, four hundred eighty-seven".