215871620 has 12 divisors (see below), whose sum is σ = 453330444. Its totient is φ = 86348640.

The previous prime is 215871613. The next prime is 215871671. The reversal of 215871620 is 26178512.

215871620 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 106543684 + 109327936 = 10322^2 + 10456^2 .

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, 5396771 + ... + 5396810.

It is an arithmetic number, because the mean of its divisors is an integer number (37777537).

Almost surely, 2^215871620 is an apocalyptic number.

215871620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215871620 is an abundant number, since it is smaller than the sum of its proper divisors (237458824).

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

215871620 is a wasteful number, since it uses less digits than its factorization.

215871620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10793590 (or 10793588 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 32.

The square root of 215871620 is about 14692.5702312427. The cubic root of 215871620 is about 599.8811060716.

The spelling of 215871620 in words is "two hundred fifteen million, eight hundred seventy-one thousand, six hundred twenty".