215686152864 has 768 divisors, whose sum is σ = 791452892160. Its totient is φ = 55638835200.

The previous prime is 215686152859. The next prime is 215686152881. The reversal of 215686152864 is 468251686512.

215686152864 is a `hidden beast` number, since 2 + 1 + 56 + 8 + 6 + 1 + 528 + 64 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 215686152864.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1246740682 + ... + 1246740854.

It is an arithmetic number, because the mean of its divisors is an integer number (1030537620).

Almost surely, 2^215686152864 is an apocalyptic number.

215686152864 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 215686152864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (395726446080).

215686152864 is an abundant number, since it is smaller than the sum of its proper divisors (575766739296).

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

215686152864 is a wasteful number, since it uses less digits than its factorization.

215686152864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 470 (or 456 counting only the distinct ones).

The product of its digits is 5529600, while the sum is 54.

The spelling of 215686152864 in words is "two hundred fifteen billion, six hundred eighty-six million, one hundred fifty-two thousand, eight hundred sixty-four".