21967199 has 2 divisors, whose sum is σ = 21967200. Its totient is φ = 21967198.

The previous prime is 21967193. The next prime is 21967229. The reversal of 21967199 is 99176912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21967199 - 2¹² = 21963103 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21967193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10983599 + 10983600.

It is an arithmetic number, because the mean of its divisors is an integer number (10983600).

Almost surely, 2^21967199 is an apocalyptic number.

21967199 is a deficient number, since it is larger than the sum of its proper divisors (1).

21967199 is an equidigital number, since it uses as much as digits as its factorization.

21967199 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 61236, while the sum is 44.

The square root of 21967199 is about 4686.9178571850. The cubic root of 21967199 is about 280.0646066903.

The spelling of 21967199 in words is "twenty-one million, nine hundred sixty-seven thousand, one hundred ninety-nine".