21056022139 has 8 divisors (see below), whose sum is σ = 21095874560. Its totient is φ = 21016195200.

The previous prime is 21056022041. The next prime is 21056022149. The reversal of 21056022139 is 93122065012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21056022139 - 2¹³ = 21056013947 is a prime.

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 21056022139.

It is not an unprimeable number, because it can be changed into a prime (21056022149) 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 7 ways as a sum of consecutive naturals, for example, 2566534 + ... + 2574724.

It is an arithmetic number, because the mean of its divisors is an integer number (2636984320).

Almost surely, 2^21056022139 is an apocalyptic number.

21056022139 is a deficient number, since it is larger than the sum of its proper divisors (39852421).

21056022139 is an equidigital number, since it uses as much as digits as its factorization.

21056022139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12741.

The product of its (nonzero) digits is 6480, while the sum is 31.

The spelling of 21056022139 in words is "twenty-one billion, fifty-six million, twenty-two thousand, one hundred thirty-nine".