215901215 has 4 divisors (see below), whose sum is σ = 259081464. Its totient is φ = 172720968.

The previous prime is 215901193. The next prime is 215901227. The reversal of 215901215 is 512109512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 215901215 - 2²⁶ = 148792351 is a prime.

It is a super-2 number, since 2×215901215² = 93226669276952450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21590117 + ... + 21590126.

It is an arithmetic number, because the mean of its divisors is an integer number (64770366).

Almost surely, 2^215901215 is an apocalyptic number.

215901215 is a deficient number, since it is larger than the sum of its proper divisors (43180249).

215901215 is an equidigital number, since it uses as much as digits as its factorization.

215901215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43180248.

The product of its (nonzero) digits is 900, while the sum is 26.

The square root of 215901215 is about 14693.5773384156. The cubic root of 215901215 is about 599.9085184600.

The spelling of 215901215 in words is "two hundred fifteen million, nine hundred one thousand, two hundred fifteen".