20516722170172 has 12 divisors (see below), whose sum is σ = 35905758544656. Its totient is φ = 10257934014560.

The previous prime is 20516722170137. The next prime is 20516722170181. The reversal of 20516722170172 is 27107122761502.

It is a super-2 number, since 2×20516722170172² (a number of 27 digits) contains 22 as substring.

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, 106659529 + ... + 106851712.

It is an arithmetic number, because the mean of its divisors is an integer number (2992146545388).

Almost surely, 2^{20516722170172} is an apocalyptic number.

It is an amenable number.

20516722170172 is a deficient number, since it is larger than the sum of its proper divisors (15389036374484).

20516722170172 is a wasteful number, since it uses less digits than its factorization.

20516722170172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213535268 (or 213535266 counting only the distinct ones).

The product of its (nonzero) digits is 164640, while the sum is 43.

The spelling of 20516722170172 in words is "twenty trillion, five hundred sixteen billion, seven hundred twenty-two million, one hundred seventy thousand, one hundred seventy-two".