21083487231 has 4 divisors (see below), whose sum is σ = 28111316312. Its totient is φ = 14055658152.

The previous prime is 21083487181. The next prime is 21083487233. The reversal of 21083487231 is 13278438012.

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

It is not a de Polignac number, because 21083487231 - 2⁶ = 21083487167 is a prime.

It is a super-2 number, since 2×21083487231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21083487231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21083487233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3513914536 + ... + 3513914541.

It is an arithmetic number, because the mean of its divisors is an integer number (7027829078).

Almost surely, 2^21083487231 is an apocalyptic number.

21083487231 is a deficient number, since it is larger than the sum of its proper divisors (7027829081).

21083487231 is an equidigital number, since it uses as much as digits as its factorization.

21083487231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7027829080.

The product of its (nonzero) digits is 64512, while the sum is 39.

The spelling of 21083487231 in words is "twenty-one billion, eighty-three million, four hundred eighty-seven thousand, two hundred thirty-one".