251369 has 4 divisors (see below), whose sum is σ = 252996. Its totient is φ = 249744.

The previous prime is 251359. The next prime is 251387. The reversal of 251369 is 963152.

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

It can be written as a sum of positive squares in 2 ways, for example, as 238144 + 13225 = 488^2 + 115^2 .

It is a cyclic number.

It is not a de Polignac number, because 251369 - 2⁴ = 251353 is a prime.

It is a super-2 number, since 2×251369² = 126372748322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (251359) 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, 554 + ... + 899.

It is an arithmetic number, because the mean of its divisors is an integer number (63249).

2²⁵¹³⁶⁹ is an apocalyptic number.

It is an amenable number.

251369 is a deficient number, since it is larger than the sum of its proper divisors (1627).

251369 is a wasteful number, since it uses less digits than its factorization.

251369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1626.

The product of its digits is 1620, while the sum is 26.

The square root of 251369 is about 501.3671309530. The cubic root of 251369 is about 63.1108320326.

It can be divided in two parts, 25 and 1369, that multiplied together give a square (34225 = 185²).

The spelling of 251369 in words is "two hundred fifty-one thousand, three hundred sixty-nine".