23656421 has 4 divisors (see below), whose sum is σ = 23669952. Its totient is φ = 23642892.

The previous prime is 23656363. The next prime is 23656447. The reversal of 23656421 is 12465632.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 23656421 - 2¹⁴ = 23640037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23656481) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3671 + ... + 7796.

It is an arithmetic number, because the mean of its divisors is an integer number (5917488).

Almost surely, 2^23656421 is an apocalyptic number.

It is an amenable number.

23656421 is a deficient number, since it is larger than the sum of its proper divisors (13531).

23656421 is a wasteful number, since it uses less digits than its factorization.

23656421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13530.

The product of its digits is 8640, while the sum is 29.

The square root of 23656421 is about 4863.7866935136. The cubic root of 23656421 is about 287.0668299735.

The spelling of 23656421 in words is "twenty-three million, six hundred fifty-six thousand, four hundred twenty-one".