20849921564 has 12 divisors (see below), whose sum is σ = 36566172384. Its totient is φ = 10402443744.

The previous prime is 20849921551. The next prime is 20849921579. The reversal of 20849921564 is 46512994802.

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, 5627177 + ... + 5630880.

It is an arithmetic number, because the mean of its divisors is an integer number (3047181032).

Almost surely, 2^20849921564 is an apocalyptic number.

It is an amenable number.

20849921564 is a deficient number, since it is larger than the sum of its proper divisors (15716250820).

20849921564 is a wasteful number, since it uses less digits than its factorization.

20849921564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11258524 (or 11258522 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 50.

The spelling of 20849921564 in words is "twenty billion, eight hundred forty-nine million, nine hundred twenty-one thousand, five hundred sixty-four".