21123310199 has 2 divisors, whose sum is σ = 21123310200. Its totient is φ = 21123310198.

The previous prime is 21123310183. The next prime is 21123310253. The reversal of 21123310199 is 99101332112.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21123310199 - 2⁴ = 21123310183 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21123310139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561655099 + 10561655100.

It is an arithmetic number, because the mean of its divisors is an integer number (10561655100).

Almost surely, 2^21123310199 is an apocalyptic number.

21123310199 is a deficient number, since it is larger than the sum of its proper divisors (1).

21123310199 is an equidigital number, since it uses as much as digits as its factorization.

21123310199 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2916, while the sum is 32.

The spelling of 21123310199 in words is "twenty-one billion, one hundred twenty-three million, three hundred ten thousand, one hundred ninety-nine".