21049004879 has 8 divisors (see below), whose sum is σ = 24056884128. Its totient is φ = 18041345280.

The previous prime is 21049004843. The next prime is 21049004891. The reversal of 21049004879 is 97840094012.

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

It is a de Polignac number, because none of the positive numbers 2^k-21049004879 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21049009879) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 335699 + ... + 393435.

It is an arithmetic number, because the mean of its divisors is an integer number (3007110516).

Almost surely, 2^21049004879 is an apocalyptic number.

21049004879 is a deficient number, since it is larger than the sum of its proper divisors (3007879249).

21049004879 is an equidigital number, since it uses as much as digits as its factorization.

21049004879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109825.

The product of its (nonzero) digits is 145152, while the sum is 44.

The spelling of 21049004879 in words is "twenty-one billion, forty-nine million, four thousand, eight hundred seventy-nine".