21586822091 has 4 divisors (see below), whose sum is σ = 21796402992. Its totient is φ = 21377241192.

The previous prime is 21586822057. The next prime is 21586822097. The reversal of 21586822091 is 19022868512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21586822091 - 2⁶ = 21586822027 is a prime.

It is a super-2 number, since 2×21586822091² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21586822097) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 104790296 + ... + 104790501.

It is an arithmetic number, because the mean of its divisors is an integer number (5449100748).

Almost surely, 2^21586822091 is an apocalyptic number.

21586822091 is a deficient number, since it is larger than the sum of its proper divisors (209580901).

21586822091 is a wasteful number, since it uses less digits than its factorization.

21586822091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209580900.

The product of its (nonzero) digits is 138240, while the sum is 44.

The spelling of 21586822091 in words is "twenty-one billion, five hundred eighty-six million, eight hundred twenty-two thousand, ninety-one".