20906687668 has 12 divisors (see below), whose sum is σ = 36770557600. Its totient is φ = 10400814072.

The previous prime is 20906687663. The next prime is 20906687693. The reversal of 20906687668 is 86678660902.

It is a hoax number, since the sum of its digits (58) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20906687663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13131546 + ... + 13133137.

Almost surely, 2^20906687668 is an apocalyptic number.

It is an amenable number.

20906687668 is a deficient number, since it is larger than the sum of its proper divisors (15863869932).

20906687668 is a wasteful number, since it uses less digits than its factorization.

20906687668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26264886 (or 26264884 counting only the distinct ones).

The product of its (nonzero) digits is 10450944, while the sum is 58.

The spelling of 20906687668 in words is "twenty billion, nine hundred six million, six hundred eighty-seven thousand, six hundred sixty-eight".