23663926421 has 2 divisors, whose sum is σ = 23663926422. Its totient is φ = 23663926420.

The previous prime is 23663926399. The next prime is 23663926463. The reversal of 23663926421 is 12462936632.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20453004196 + 3210922225 = 143014^2 + 56665^2 .

It is a cyclic number.

It is not a de Polignac number, because 23663926421 - 2¹⁴ = 23663910037 is a prime.

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 (23663926721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11831963210 + 11831963211.

It is an arithmetic number, because the mean of its divisors is an integer number (11831963211).

Almost surely, 2^23663926421 is an apocalyptic number.

It is an amenable number.

23663926421 is a deficient number, since it is larger than the sum of its proper divisors (1).

23663926421 is an equidigital number, since it uses as much as digits as its factorization.

23663926421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 559872, while the sum is 44.

The spelling of 23663926421 in words is "twenty-three billion, six hundred sixty-three million, nine hundred twenty-six thousand, four hundred twenty-one".