23705621 has 2 divisors, whose sum is σ = 23705622. Its totient is φ = 23705620.

The previous prime is 23705593. The next prime is 23705623. The reversal of 23705621 is 12650732.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12888100 + 10817521 = 3590^2 + 3289^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23705621 is a prime.

Together with 23705623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23705623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11852810 + 11852811.

It is an arithmetic number, because the mean of its divisors is an integer number (11852811).

Almost surely, 2^23705621 is an apocalyptic number.

It is an amenable number.

23705621 is a deficient number, since it is larger than the sum of its proper divisors (1).

23705621 is an equidigital number, since it uses as much as digits as its factorization.

23705621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2520, while the sum is 26.

The square root of 23705621 is about 4868.8418540758. The cubic root of 23705621 is about 287.2657035052.

The spelling of 23705621 in words is "twenty-three million, seven hundred five thousand, six hundred twenty-one".