21923193 has 4 divisors (see below), whose sum is σ = 29230928. Its totient is φ = 14615460.

The previous prime is 21923179. The next prime is 21923227. The reversal of 21923193 is 39132912.

It is a happy number.

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 not a de Polignac number, because 21923193 - 2⁸ = 21922937 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 21923193.

It is not an unprimeable number, because it can be changed into a prime (21923173) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3653863 + ... + 3653868.

It is an arithmetic number, because the mean of its divisors is an integer number (7307732).

Almost surely, 2^21923193 is an apocalyptic number.

It is an amenable number.

21923193 is a deficient number, since it is larger than the sum of its proper divisors (7307735).

21923193 is an equidigital number, since it uses as much as digits as its factorization.

21923193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7307734.

The product of its digits is 2916, while the sum is 30.

The square root of 21923193 is about 4682.2209473710. The cubic root of 21923193 is about 279.8774676443.

The spelling of 21923193 in words is "twenty-one million, nine hundred twenty-three thousand, one hundred ninety-three".