215551251 has 12 divisors (see below), whose sum is σ = 312169728. Its totient is φ = 143323344.

The previous prime is 215551241. The next prime is 215551267. The reversal of 215551251 is 152155512.

It is not a de Polignac number, because 215551251 - 2¹¹ = 215549203 is a prime.

It is not an unprimeable number, because it can be changed into a prime (215551241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27820 + ... + 34713.

It is an arithmetic number, because the mean of its divisors is an integer number (26014144).

Almost surely, 2^215551251 is an apocalyptic number.

215551251 is a deficient number, since it is larger than the sum of its proper divisors (96618477).

215551251 is a wasteful number, since it uses less digits than its factorization.

215551251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62922 (or 62919 counting only the distinct ones).

The product of its digits is 2500, while the sum is 27.

The square root of 215551251 is about 14681.6637681157. The cubic root of 215551251 is about 599.5842035888.

The spelling of 215551251 in words is "two hundred fifteen million, five hundred fifty-one thousand, two hundred fifty-one".