215973178612 has 12 divisors (see below), whose sum is σ = 378031852800. Its totient is φ = 107964077816.

The previous prime is 215973178609. The next prime is 215973178621. The reversal of 215973178612 is 216871379512.

It is a self number, because there is not a number n which added to its sum of digits gives 215973178612.

It is a congruent number.

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, 5606278 + ... + 5644669.

It is an arithmetic number, because the mean of its divisors is an integer number (31502654400).

Almost surely, 2^215973178612 is an apocalyptic number.

It is an amenable number.

215973178612 is a deficient number, since it is larger than the sum of its proper divisors (162058674188).

215973178612 is a wasteful number, since it uses less digits than its factorization.

215973178612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11255750 (or 11255748 counting only the distinct ones).

The product of its digits is 1270080, while the sum is 52.

Subtracting 215973178612 from its reverse (216871379512), we obtain a square (898200900 = 29970²).

The spelling of 215973178612 in words is "two hundred fifteen billion, nine hundred seventy-three million, one hundred seventy-eight thousand, six hundred twelve".