21783567923 has 32 divisors (see below), whose sum is σ = 24473064000. Its totient is φ = 19258477056.

The previous prime is 21783567913. The next prime is 21783567941. The reversal of 21783567923 is 32976538712.

It is a happy number.

It is not a de Polignac number, because 21783567923 - 2⁴ = 21783567907 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21783567913) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8544653 + ... + 8547201.

It is an arithmetic number, because the mean of its divisors is an integer number (764783250).

Almost surely, 2^21783567923 is an apocalyptic number.

21783567923 is a deficient number, since it is larger than the sum of its proper divisors (2689496077).

21783567923 is a wasteful number, since it uses less digits than its factorization.

21783567923 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2871.

The product of its digits is 3810240, while the sum is 53.

The spelling of 21783567923 in words is "twenty-one billion, seven hundred eighty-three million, five hundred sixty-seven thousand, nine hundred twenty-three".