215561105578 has 128 divisors (see below), whose sum is σ = 428648951808. Its totient is φ = 78879550464.

The previous prime is 215561105509. The next prime is 215561105579. The reversal of 215561105578 is 875501165512.

It is not an unprimeable number, because it can be changed into a prime (215561105579) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 116707851 + ... + 116709697.

It is an arithmetic number, because the mean of its divisors is an integer number (3348819936).

Almost surely, 2^215561105578 is an apocalyptic number.

215561105578 is a deficient number, since it is larger than the sum of its proper divisors (213087846230).

215561105578 is a wasteful number, since it uses less digits than its factorization.

215561105578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2516.

The product of its (nonzero) digits is 420000, while the sum is 46.

The spelling of 215561105578 in words is "two hundred fifteen billion, five hundred sixty-one million, one hundred five thousand, five hundred seventy-eight".