251098780265 has 4 divisors (see below), whose sum is σ = 301318536324. Its totient is φ = 200879024208.

The previous prime is 251098780259. The next prime is 251098780319. The reversal of 251098780265 is 562087890152.

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 136007539264 + 115091241001 = 368792^2 + 339251^2 .

It is a cyclic number.

It is not a de Polignac number, because 251098780265 - 2⁴ = 251098780249 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25109878022 + ... + 25109878031.

It is an arithmetic number, because the mean of its divisors is an integer number (75329634081).

Almost surely, 2^251098780265 is an apocalyptic number.

It is an amenable number.

251098780265 is a deficient number, since it is larger than the sum of its proper divisors (50219756059).

251098780265 is an equidigital number, since it uses as much as digits as its factorization.

251098780265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50219756058.

The product of its (nonzero) digits is 2419200, while the sum is 53.

The spelling of 251098780265 in words is "two hundred fifty-one billion, ninety-eight million, seven hundred eighty thousand, two hundred sixty-five".