215131278 has 32 divisors (see below), whose sum is σ = 437875200. Its totient is φ = 70449120.

The previous prime is 215131253. The next prime is 215131307. The reversal of 215131278 is 872131512.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 147951 + ... + 149397.

It is an arithmetic number, because the mean of its divisors is an integer number (13683600).

Almost surely, 2^215131278 is an apocalyptic number.

215131278 is an abundant number, since it is smaller than the sum of its proper divisors (222743922).

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

215131278 is a wasteful number, since it uses less digits than its factorization.

215131278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1872.

The product of its digits is 3360, while the sum is 30.

The square root of 215131278 is about 14667.3541581295. The cubic root of 215131278 is about 599.1945470041.

It can be divided in two parts, 21513 and 1278, that added together give a triangular number (22791 = T₂₁₃).

The spelling of 215131278 in words is "two hundred fifteen million, one hundred thirty-one thousand, two hundred seventy-eight".