215875891 has 16 divisors (see below), whose sum is σ = 283311360. Its totient is φ = 159360480.

The previous prime is 215875859. The next prime is 215875897. The reversal of 215875891 is 198578512.

It is a cyclic number.

It is not a de Polignac number, because 215875891 - 2⁵ = 215875859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215875897) 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 15 ways as a sum of consecutive naturals, for example, 72316 + ... + 75241.

It is an arithmetic number, because the mean of its divisors is an integer number (17706960).

Almost surely, 2^215875891 is an apocalyptic number.

215875891 is a deficient number, since it is larger than the sum of its proper divisors (67435469).

215875891 is a wasteful number, since it uses less digits than its factorization.

215875891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147594.

The product of its digits is 201600, while the sum is 46.

The square root of 215875891 is about 14692.7155760942. The cubic root of 215875891 is about 599.8850622429.

The spelling of 215875891 in words is "two hundred fifteen million, eight hundred seventy-five thousand, eight hundred ninety-one".