251298840 has 128 divisors (see below), whose sum is σ = 831902400. Its totient is φ = 60334080.

The previous prime is 251298829. The next prime is 251298847. The reversal of 251298840 is 48892152.

It is a super-2 number, since 2×251298840² = 126302213970691200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251298847) 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 31 ways as a sum of consecutive naturals, for example, 61996 + ... + 65924.

Almost surely, 2^251298840 is an apocalyptic number.

251298840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 251298840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (415951200).

251298840 is an abundant number, since it is smaller than the sum of its proper divisors (580603560).

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

251298840 is a wasteful number, since it uses less digits than its factorization.

251298840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3997 (or 3993 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 39.

The square root of 251298840 is about 15852.4080189730. The cubic root of 251298840 is about 631.0495983142.

The spelling of 251298840 in words is "two hundred fifty-one million, two hundred ninety-eight thousand, eight hundred forty".