21793223 has 2 divisors, whose sum is σ = 21793224. Its totient is φ = 21793222.

The previous prime is 21793183. The next prime is 21793231. The reversal of 21793223 is 32239712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21793223 - 2⁶ = 21793159 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21793253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10896611 + 10896612.

It is an arithmetic number, because the mean of its divisors is an integer number (10896612).

Almost surely, 2^21793223 is an apocalyptic number.

21793223 is a deficient number, since it is larger than the sum of its proper divisors (1).

21793223 is an equidigital number, since it uses as much as digits as its factorization.

21793223 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4536, while the sum is 29.

The square root of 21793223 is about 4668.3212185967. The cubic root of 21793223 is about 279.3232935686.

The spelling of 21793223 in words is "twenty-one million, seven hundred ninety-three thousand, two hundred twenty-three".