21872732723 has 2 divisors, whose sum is σ = 21872732724. Its totient is φ = 21872732722.

The previous prime is 21872732719. The next prime is 21872732801. The reversal of 21872732723 is 32723727812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21872732723 - 2² = 21872732719 is a prime.

It is not a weakly prime, because it can be changed into another prime (21872702723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10936366361 + 10936366362.

It is an arithmetic number, because the mean of its divisors is an integer number (10936366362).

Almost surely, 2^21872732723 is an apocalyptic number.

21872732723 is a deficient number, since it is larger than the sum of its proper divisors (1).

21872732723 is an equidigital number, since it uses as much as digits as its factorization.

21872732723 is an evil number, because the sum of its binary digits is even.

The product of its digits is 395136, while the sum is 44.

The spelling of 21872732723 in words is "twenty-one billion, eight hundred seventy-two million, seven hundred thirty-two thousand, seven hundred twenty-three".