21912479739 has 12 divisors (see below), whose sum is σ = 31655832000. Its totient is φ = 14606255664.

The previous prime is 21912479737. The next prime is 21912479747. The reversal of 21912479739 is 93797421912.

It is a happy number.

It is not a de Polignac number, because 21912479739 - 2¹ = 21912479737 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21912479737) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 103339 + ... + 233460.

It is an arithmetic number, because the mean of its divisors is an integer number (2637986000).

Almost surely, 2^21912479739 is an apocalyptic number.

21912479739 is a deficient number, since it is larger than the sum of its proper divisors (9743352261).

21912479739 is a wasteful number, since it uses less digits than its factorization.

21912479739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 344034 (or 344031 counting only the distinct ones).

The product of its digits is 1714608, while the sum is 54.

The spelling of 21912479739 in words is "twenty-one billion, nine hundred twelve million, four hundred seventy-nine thousand, seven hundred thirty-nine".