21806090677 has 16 divisors (see below), whose sum is σ = 27373455360. Its totient is φ = 16937320752.

The previous prime is 21806090623. The next prime is 21806090693. The reversal of 21806090677 is 77609060812.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21806090677 is a prime.

It is a super-2 number, since 2×21806090677² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21806090177) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3561193 + ... + 3567310.

It is an arithmetic number, because the mean of its divisors is an integer number (1710840960).

Almost surely, 2^21806090677 is an apocalyptic number.

It is an amenable number.

21806090677 is a deficient number, since it is larger than the sum of its proper divisors (5567364683).

21806090677 is a wasteful number, since it uses less digits than its factorization.

21806090677 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7128552.

The product of its (nonzero) digits is 254016, while the sum is 46.

The spelling of 21806090677 in words is "twenty-one billion, eight hundred six million, ninety thousand, six hundred seventy-seven".