23778921 has 8 divisors (see below), whose sum is σ = 32106880. Its totient is φ = 15651792.

The previous prime is 23778917. The next prime is 23778943. The reversal of 23778921 is 12987732.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 23778921 - 2² = 23778917 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 23778921.

It is not an unprimeable number, because it can be changed into a prime (23778991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49930 + ... + 50403.

It is an arithmetic number, because the mean of its divisors is an integer number (4013360).

Almost surely, 2^23778921 is an apocalyptic number.

It is an amenable number.

23778921 is a deficient number, since it is larger than the sum of its proper divisors (8327959).

23778921 is a wasteful number, since it uses less digits than its factorization.

23778921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100415.

The product of its digits is 42336, while the sum is 39.

The square root of 23778921 is about 4876.3635016270. The cubic root of 23778921 is about 287.5614830069.

The spelling of 23778921 in words is "twenty-three million, seven hundred seventy-eight thousand, nine hundred twenty-one".