251396945 has 8 divisors (see below), whose sum is σ = 302573544. Its totient is φ = 200519424.

The previous prime is 251396939. The next prime is 251396983. The reversal of 251396945 is 549693152.

251396945 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 3775249 + 247621696 = 1943^2 + 15736^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 251396945 - 2⁸ = 251396689 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 251396896 and 251396905.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72914 + ... + 76283.

It is an arithmetic number, because the mean of its divisors is an integer number (37821693).

Almost surely, 2^251396945 is an apocalyptic number.

It is an amenable number.

251396945 is a deficient number, since it is larger than the sum of its proper divisors (51176599).

251396945 is a wasteful number, since it uses less digits than its factorization.

251396945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149539.

The product of its digits is 291600, while the sum is 44.

The square root of 251396945 is about 15855.5020418781. The cubic root of 251396945 is about 631.1317064877.

The spelling of 251396945 in words is "two hundred fifty-one million, three hundred ninety-six thousand, nine hundred forty-five".