251289216 has 112 divisors (see below), whose sum is σ = 750858210. Its totient is φ = 83731968.

The previous prime is 251289211. The next prime is 251289229. The reversal of 251289216 is 612982152.

It can be written as a sum of positive squares in only one way, i.e., 222129216 + 29160000 = 14904^2 + 5400^2 .

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

It is not an unprimeable number, because it can be changed into a prime (251289211) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 91966 + ... + 94658.

Almost surely, 2^251289216 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 251289216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (375429105).

251289216 is an abundant number, since it is smaller than the sum of its proper divisors (499568994).

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

251289216 is an frugal number, since it uses more digits than its factorization.

251289216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2725 (or 2698 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 251289216 is about 15852.1044659692. The cubic root of 251289216 is about 631.0415424355.

The spelling of 251289216 in words is "two hundred fifty-one million, two hundred eighty-nine thousand, two hundred sixteen".