21221020199 has 2 divisors, whose sum is σ = 21221020200. Its totient is φ = 21221020198.

The previous prime is 21221020189. The next prime is 21221020201. The reversal of 21221020199 is 99102012212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21221020199 - 2³² = 16926052903 is a prime.

Together with 21221020201, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21221020189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610510099 + 10610510100.

It is an arithmetic number, because the mean of its divisors is an integer number (10610510100).

Almost surely, 2^21221020199 is an apocalyptic number.

21221020199 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221020199 is an equidigital number, since it uses as much as digits as its factorization.

21221020199 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 29.

The spelling of 21221020199 in words is "twenty-one billion, two hundred twenty-one million, twenty thousand, one hundred ninety-nine".