21836648723 has 4 divisors (see below), whose sum is σ = 22589636640. Its totient is φ = 21083660808.

The previous prime is 21836648711. The next prime is 21836648737. The reversal of 21836648723 is 32784663812.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21836648723 - 2⁸ = 21836648467 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21836638723) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 376493915 + ... + 376493972.

It is an arithmetic number, because the mean of its divisors is an integer number (5647409160).

Almost surely, 2^21836648723 is an apocalyptic number.

21836648723 is a deficient number, since it is larger than the sum of its proper divisors (752987917).

21836648723 is an equidigital number, since it uses as much as digits as its factorization.

21836648723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 752987916.

The product of its digits is 2322432, while the sum is 50.

The spelling of 21836648723 in words is "twenty-one billion, eight hundred thirty-six million, six hundred forty-eight thousand, seven hundred twenty-three".