215525988864 has 160 divisors (see below), whose sum is σ = 665710784640. Its totient is φ = 68718329856.

The previous prime is 215525988793. The next prime is 215525988877. The reversal of 215525988864 is 468889525512.

It is a happy number.

215525988864 is a `hidden beast` number, since 2 + 15 + 525 + 98 + 8 + 8 + 6 + 4 = 666.

215525988864 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20977 + ... + 656880.

It is an arithmetic number, because the mean of its divisors is an integer number (4160692404).

Almost surely, 2^215525988864 is an apocalyptic number.

215525988864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 215525988864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (332855392320).

215525988864 is an abundant number, since it is smaller than the sum of its proper divisors (450184795776).

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

215525988864 is an equidigital number, since it uses as much as digits as its factorization.

215525988864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 677907 (or 677885 counting only the distinct ones).

The product of its digits is 55296000, while the sum is 63.

The spelling of 215525988864 in words is "two hundred fifteen billion, five hundred twenty-five million, nine hundred eighty-eight thousand, eight hundred sixty-four".