215855872 has 36 divisors (see below), whose sum is σ = 440911240. Its totient is φ = 105412608.

The previous prime is 215855869. The next prime is 215855873. The reversal of 215855872 is 278558512.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is not an unprimeable number, because it can be changed into a prime (215855873) 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 3 ways as a sum of consecutive naturals, for example, 1204 + ... + 20812.

Almost surely, 2^215855872 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 215855872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (220455620).

215855872 is an abundant number, since it is smaller than the sum of its proper divisors (225055368).

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

215855872 is an equidigital number, since it uses as much as digits as its factorization.

215855872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19668 (or 19654 counting only the distinct ones).

The product of its digits is 224000, while the sum is 43.

The square root of 215855872 is about 14692.0343043433. The cubic root of 215855872 is about 599.8665184548.

The spelling of 215855872 in words is "two hundred fifteen million, eight hundred fifty-five thousand, eight hundred seventy-two".