21808531283 has 24 divisors (see below), whose sum is σ = 27778457520. Its totient is φ = 16930374720.

The previous prime is 21808531273. The next prime is 21808531291. The reversal of 21808531283 is 38213580812.

It is not a de Polignac number, because 21808531283 - 2⁴ = 21808531267 is a prime.

It is a super-2 number, since 2×21808531283² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21808531283.

It is not an unprimeable number, because it can be changed into a prime (21808531223) 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 23 ways as a sum of consecutive naturals, for example, 69785 + ... + 220197.

It is an arithmetic number, because the mean of its divisors is an integer number (1157435730).

Almost surely, 2^21808531283 is an apocalyptic number.

21808531283 is a deficient number, since it is larger than the sum of its proper divisors (5969926237).

21808531283 is a wasteful number, since it uses less digits than its factorization.

21808531283 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150707 (or 150700 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 41.

The spelling of 21808531283 in words is "twenty-one billion, eight hundred eight million, five hundred thirty-one thousand, two hundred eighty-three".