21736717123 has 16 divisors (see below), whose sum is σ = 25342326144. Its totient is φ = 18424428160.

The previous prime is 21736717109. The next prime is 21736717139. The reversal of 21736717123 is 32171763712.

It is a cyclic number.

It is not a de Polignac number, because 21736717123 - 2³³ = 13146782531 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21736717183) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 523165 + ... + 563182.

It is an arithmetic number, because the mean of its divisors is an integer number (1583895384).

Almost surely, 2^21736717123 is an apocalyptic number.

21736717123 is a deficient number, since it is larger than the sum of its proper divisors (3605609021).

21736717123 is a wasteful number, since it uses less digits than its factorization.

21736717123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1086482.

The product of its digits is 74088, while the sum is 40.

The spelling of 21736717123 in words is "twenty-one billion, seven hundred thirty-six million, seven hundred seventeen thousand, one hundred twenty-three".