23689440821 has 2 divisors, whose sum is σ = 23689440822. Its totient is φ = 23689440820.

The previous prime is 23689440811. The next prime is 23689440833. The reversal of 23689440821 is 12804498632.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23131063921 + 558376900 = 152089^2 + 23630^2 .

It is a cyclic number.

It is not a de Polignac number, because 23689440821 - 2³⁰ = 22615698997 is a prime.

It is a super-2 number, since 2×23689440821² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23689440811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11844720410 + 11844720411.

It is an arithmetic number, because the mean of its divisors is an integer number (11844720411).

Almost surely, 2^23689440821 is an apocalyptic number.

It is an amenable number.

23689440821 is a deficient number, since it is larger than the sum of its proper divisors (1).

23689440821 is an equidigital number, since it uses as much as digits as its factorization.

23689440821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 663552, while the sum is 47.

The spelling of 23689440821 in words is "twenty-three billion, six hundred eighty-nine million, four hundred forty thousand, eight hundred twenty-one".