21044947179 has 4 divisors (see below), whose sum is σ = 28059929576. Its totient is φ = 14029964784.

The previous prime is 21044947177. The next prime is 21044947201. The reversal of 21044947179 is 97174944012.

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

It is not a de Polignac number, because 21044947179 - 2¹ = 21044947177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21044947177) 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, 3507491194 + ... + 3507491199.

It is an arithmetic number, because the mean of its divisors is an integer number (7014982394).

Almost surely, 2^21044947179 is an apocalyptic number.

21044947179 is a deficient number, since it is larger than the sum of its proper divisors (7014982397).

21044947179 is an equidigital number, since it uses as much as digits as its factorization.

21044947179 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7014982396.

The product of its (nonzero) digits is 508032, while the sum is 48.

The spelling of 21044947179 in words is "twenty-one billion, forty-four million, nine hundred forty-seven thousand, one hundred seventy-nine".