251497 has 4 divisors (see below), whose sum is σ = 256896. Its totient is φ = 246100.

The previous prime is 251491. The next prime is 251501. The reversal of 251497 is 794152.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 251497 - 2¹¹ = 249449 is a prime.

It is a Duffinian number.

251497 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (251491) 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 3 ways as a sum of consecutive naturals, for example, 2629 + ... + 2722.

It is an arithmetic number, because the mean of its divisors is an integer number (64224).

2²⁵¹⁴⁹⁷ is an apocalyptic number.

It is an amenable number.

251497 is a deficient number, since it is larger than the sum of its proper divisors (5399).

251497 is an equidigital number, since it uses as much as digits as its factorization.

251497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5398.

The product of its digits is 2520, while the sum is 28.

The square root of 251497 is about 501.4947656756. The cubic root of 251497 is about 63.1215424698.

The spelling of 251497 in words is "two hundred fifty-one thousand, four hundred ninety-seven".