251216251 has 16 divisors (see below), whose sum is σ = 295787520. Its totient is φ = 210345120.

The previous prime is 251216249. The next prime is 251216261. The reversal of 251216251 is 152612152.

It is a cyclic number.

It is not a de Polignac number, because 251216251 - 2¹ = 251216249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (251216261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 73110 + ... + 76468.

It is an arithmetic number, because the mean of its divisors is an integer number (18486720).

Almost surely, 2^251216251 is an apocalyptic number.

251216251 is a deficient number, since it is larger than the sum of its proper divisors (44571269).

251216251 is a wasteful number, since it uses less digits than its factorization.

251216251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3906.

The product of its digits is 1200, while the sum is 25.

The square root of 251216251 is about 15849.8028694366. The cubic root of 251216251 is about 630.9804595605.

The spelling of 251216251 in words is "two hundred fifty-one million, two hundred sixteen thousand, two hundred fifty-one".