251164465 has 4 divisors (see below), whose sum is σ = 301397364. Its totient is φ = 200931568.

The previous prime is 251164453. The next prime is 251164513. The reversal of 251164465 is 564461152.

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 121022001 + 130142464 = 11001^2 + 11408^2 .

It is a cyclic number.

It is not a de Polignac number, because 251164465 - 2⁷ = 251164337 is a prime.

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 251164465.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25116442 + ... + 25116451.

It is an arithmetic number, because the mean of its divisors is an integer number (75349341).

Almost surely, 2^251164465 is an apocalyptic number.

It is an amenable number.

251164465 is a deficient number, since it is larger than the sum of its proper divisors (50232899).

251164465 is an equidigital number, since it uses as much as digits as its factorization.

251164465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50232898.

The product of its digits is 28800, while the sum is 34.

The square root of 251164465 is about 15848.1691371590. The cubic root of 251164465 is about 630.9370995742.

The spelling of 251164465 in words is "two hundred fifty-one million, one hundred sixty-four thousand, four hundred sixty-five".