23440365821 has 2 divisors, whose sum is σ = 23440365822. Its totient is φ = 23440365820.

The previous prime is 23440365811. The next prime is 23440365847. The reversal of 23440365821 is 12856304432.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23313014596 + 127351225 = 152686^2 + 11285^2 .

It is a cyclic number.

It is not a de Polignac number, because 23440365821 - 2¹⁴ = 23440349437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23440365811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11720182910 + 11720182911.

It is an arithmetic number, because the mean of its divisors is an integer number (11720182911).

Almost surely, 2^23440365821 is an apocalyptic number.

It is an amenable number.

23440365821 is a deficient number, since it is larger than the sum of its proper divisors (1).

23440365821 is an equidigital number, since it uses as much as digits as its factorization.

23440365821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 138240, while the sum is 38.

The spelling of 23440365821 in words is "twenty-three billion, four hundred forty million, three hundred sixty-five thousand, eight hundred twenty-one".