251399052 has 72 divisors (see below), whose sum is σ = 673161216. Its totient is φ = 82001808.

The previous prime is 251399041. The next prime is 251399063. The reversal of 251399052 is 250993152.

It is a happy number.

251399052 is a `hidden beast` number, since 2 + 513 + 9 + 90 + 52 = 666.

It is an interprime number because it is at equal distance from previous prime (251399041) and next prime (251399063).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 251398998 and 251399016.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 42933 + ... + 48435.

Almost surely, 2^251399052 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 251399052, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (336580608).

251399052 is an abundant number, since it is smaller than the sum of its proper divisors (421762164).

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

251399052 is a wasteful number, since it uses less digits than its factorization.

251399052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5569 (or 5555 counting only the distinct ones).

The product of its (nonzero) digits is 24300, while the sum is 36.

The square root of 251399052 is about 15855.5684855511. The cubic root of 251399052 is about 631.1334696897.

It can be divided in two parts, 25139 and 9052, that added together give a triangular number (34191 = T₂₆₁).

The spelling of 251399052 in words is "two hundred fifty-one million, three hundred ninety-nine thousand, fifty-two".