21200021170 has 16 divisors (see below), whose sum is σ = 38162822400. Its totient is φ = 8479389744.

The previous prime is 21200021149. The next prime is 21200021189. The reversal of 21200021170 is 7112000212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82249 + ... + 221731.

It is an arithmetic number, because the mean of its divisors is an integer number (2385176400).

Almost surely, 2^21200021170 is an apocalyptic number.

21200021170 is a deficient number, since it is larger than the sum of its proper divisors (16962801230).

21200021170 is a wasteful number, since it uses less digits than its factorization.

21200021170 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154689.

The product of its (nonzero) digits is 56, while the sum is 16.

Adding to 21200021170 its reverse (7112000212), we get a palindrome (28312021382).

The spelling of 21200021170 in words is "twenty-one billion, two hundred million, twenty-one thousand, one hundred seventy".