21193223 has 2 divisors, whose sum is σ = 21193224. Its totient is φ = 21193222.

The previous prime is 21193217. The next prime is 21193231. The reversal of 21193223 is 32239112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21193223 - 2⁸ = 21192967 is a prime.

It is a super-2 number, since 2×21193223² = 898305402255458, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21193253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10596611 + 10596612.

It is an arithmetic number, because the mean of its divisors is an integer number (10596612).

It is a self-describing number.

Almost surely, 2^21193223 is an apocalyptic number.

21193223 is a deficient number, since it is larger than the sum of its proper divisors (1).

21193223 is an equidigital number, since it uses as much as digits as its factorization.

21193223 is an evil number, because the sum of its binary digits is even.

The product of its digits is 648, while the sum is 23.

The square root of 21193223 is about 4603.6097792928. The cubic root of 21193223 is about 276.7360063941.

The spelling of 21193223 in words is "twenty-one million, one hundred ninety-three thousand, two hundred twenty-three".