251972736 has 64 divisors (see below), whose sum is σ = 674546400. Its totient is φ = 83333120.

The previous prime is 251972731. The next prime is 251972741. The reversal of 251972736 is 637279152.

It is an interprime number because it is at equal distance from previous prime (251972731) and next prime (251972741).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251972731) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47800 + ... + 52808.

Almost surely, 2^251972736 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 251972736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (337273200).

251972736 is an abundant number, since it is smaller than the sum of its proper divisors (422573664).

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

251972736 is a wasteful number, since it uses less digits than its factorization.

251972736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5157 (or 5145 counting only the distinct ones).

The product of its digits is 158760, while the sum is 42.

The square root of 251972736 is about 15873.6491078769. The cubic root of 251972736 is about 631.6131799457.

The spelling of 251972736 in words is "two hundred fifty-one million, nine hundred seventy-two thousand, seven hundred thirty-six".