21342740909 has 12 divisors (see below), whose sum is σ = 24957266688. Its totient is φ = 18197991000.

The previous prime is 21342740897. The next prime is 21342740917. The reversal of 21342740909 is 90904724312.

It is not a de Polignac number, because 21342740909 - 2⁴ = 21342740893 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21342740999) 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, 1130867 + ... + 1149584.

It is an arithmetic number, because the mean of its divisors is an integer number (2079772224).

Almost surely, 2^21342740909 is an apocalyptic number.

It is an amenable number.

21342740909 is a deficient number, since it is larger than the sum of its proper divisors (3614525779).

21342740909 is a wasteful number, since it uses less digits than its factorization.

21342740909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2280656 (or 2280649 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 41.

The spelling of 21342740909 in words is "twenty-one billion, three hundred forty-two million, seven hundred forty thousand, nine hundred nine".