21424474779 has 8 divisors (see below), whose sum is σ = 28784027712. Its totient is φ = 14173952520.

The previous prime is 21424474639. The next prime is 21424474787. The reversal of 21424474779 is 97747442412.

It is a happy number.

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

It is not a de Polignac number, because 21424474779 - 2²³ = 21416086171 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21424479779) 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 7 ways as a sum of consecutive naturals, for example, 27257209 + ... + 27257994.

It is an arithmetic number, because the mean of its divisors is an integer number (3598003464).

Almost surely, 2^21424474779 is an apocalyptic number.

21424474779 is a deficient number, since it is larger than the sum of its proper divisors (7359552933).

21424474779 is a wasteful number, since it uses less digits than its factorization.

21424474779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54515337.

The product of its digits is 3161088, while the sum is 51.

The spelling of 21424474779 in words is "twenty-one billion, four hundred twenty-four million, four hundred seventy-four thousand, seven hundred seventy-nine".