20689081108 has 12 divisors (see below), whose sum is σ = 36211777812. Its totient is φ = 10342858880.

The previous prime is 20689081099. The next prime is 20689081111. The reversal of 20689081108 is 80118098602.

It can be written as a sum of positive squares in 2 ways, for example, as 2821946884 + 17867134224 = 53122^2 + 133668^2 .

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, 392533 + ... + 442108.

It is an arithmetic number, because the mean of its divisors is an integer number (3017648151).

Almost surely, 2^20689081108 is an apocalyptic number.

It is an amenable number.

20689081108 is a deficient number, since it is larger than the sum of its proper divisors (15522696704).

20689081108 is a wasteful number, since it uses less digits than its factorization.

20689081108 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 840842 (or 840840 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 43.

The spelling of 20689081108 in words is "twenty billion, six hundred eighty-nine million, eighty-one thousand, one hundred eight".