215131551 has 16 divisors (see below), whose sum is σ = 295975680. Its totient is φ = 138905280.

The previous prime is 215131529. The next prime is 215131577. The reversal of 215131551 is 155131512.

It is not a de Polignac number, because 215131551 - 2²² = 210937247 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215135551) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10806 + ... + 23388.

It is an arithmetic number, because the mean of its divisors is an integer number (18498480).

Almost surely, 2^215131551 is an apocalyptic number.

215131551 is a deficient number, since it is larger than the sum of its proper divisors (80844129).

215131551 is a wasteful number, since it uses less digits than its factorization.

215131551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12766.

The product of its digits is 750, while the sum is 24.

The square root of 215131551 is about 14667.3634645085. The cubic root of 215131551 is about 599.1948004618.

The spelling of 215131551 in words is "two hundred fifteen million, one hundred thirty-one thousand, five hundred fifty-one".