23928421 has 4 divisors (see below), whose sum is σ = 26103744. Its totient is φ = 21753100.

The previous prime is 23928419. The next prime is 23928449. The reversal of 23928421 is 12482932.

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 23928421 - 2¹ = 23928419 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 (23928481) 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, 1087645 + ... + 1087666.

It is an arithmetic number, because the mean of its divisors is an integer number (6525936).

Almost surely, 2^23928421 is an apocalyptic number.

It is an amenable number.

23928421 is a deficient number, since it is larger than the sum of its proper divisors (2175323).

23928421 is a wasteful number, since it uses less digits than its factorization.

23928421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2175322.

The product of its digits is 6912, while the sum is 31.

The square root of 23928421 is about 4891.6685292444. The cubic root of 23928421 is about 288.1628652183.

The spelling of 23928421 in words is "twenty-three million, nine hundred twenty-eight thousand, four hundred twenty-one".