251145216 has 264 divisors, whose sum is σ = 881356320. Its totient is φ = 67239936.

The previous prime is 251145197. The next prime is 251145259. The reversal of 251145216 is 612541152.

251145216 is a `hidden beast` number, since 25 + 114 + 521 + 6 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 251145216.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1096590 + ... + 1096818.

Almost surely, 2^251145216 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 251145216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (440678160).

251145216 is an abundant number, since it is smaller than the sum of its proper divisors (630211104).

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

251145216 is a wasteful number, since it uses less digits than its factorization.

251145216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279 (or 258 counting only the distinct ones).

The product of its digits is 2400, while the sum is 27.

The square root of 251145216 is about 15847.5618313985. The cubic root of 251145216 is about 630.9209810274.

Adding to 251145216 its reverse (612541152), we get a palindrome (863686368).

The spelling of 251145216 in words is "two hundred fifty-one million, one hundred forty-five thousand, two hundred sixteen".