251249280 has 64 divisors (see below), whose sum is σ = 800863200. Its totient is φ = 66999296.

The previous prime is 251249279. The next prime is 251249281. The reversal of 251249280 is 82942152.

It is an interprime number because it is at equal distance from previous prime (251249279) and next prime (251249281).

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (251249281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63510 + ... + 67349.

Almost surely, 2^251249280 is an apocalyptic number.

251249280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251249280 is an abundant number, since it is smaller than the sum of its proper divisors (549613920).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

251249280 is a wasteful number, since it uses less digits than its factorization.

251249280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130881 (or 130869 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 251249280 is about 15850.8447724404. The cubic root of 251249280 is about 631.0081113548.

The spelling of 251249280 in words is "two hundred fifty-one million, two hundred forty-nine thousand, two hundred eighty".