215808081 has 16 divisors (see below), whose sum is σ = 314500608. Its totient is φ = 131040000.

The previous prime is 215808079. The next prime is 215808101. The reversal of 215808081 is 180808512.

It is not a de Polignac number, because 215808081 - 2¹ = 215808079 is a prime.

It is a super-2 number, since 2×215808081² = 93146255649805122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (215808041) 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, 66670 + ... + 69831.

It is an arithmetic number, because the mean of its divisors is an integer number (19656288).

Almost surely, 2^215808081 is an apocalyptic number.

It is an amenable number.

215808081 is a deficient number, since it is larger than the sum of its proper divisors (98692527).

215808081 is a wasteful number, since it uses less digits than its factorization.

215808081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136552.

The product of its (nonzero) digits is 5120, while the sum is 33.

The square root of 215808081 is about 14690.4077887579. The cubic root of 215808081 is about 599.8222445658.

The spelling of 215808081 in words is "two hundred fifteen million, eight hundred eight thousand, eighty-one".