21001111020199 has 2 divisors, whose sum is σ = 21001111020200. Its totient is φ = 21001111020198.

The previous prime is 21001111020181. The next prime is 21001111020221. The reversal of 21001111020199 is 99102011110012.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21001111020199 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21001111020119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500555510099 + 10500555510100.

It is an arithmetic number, because the mean of its divisors is an integer number (10500555510100).

Almost surely, 2^{21001111020199} is an apocalyptic number.

21001111020199 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001111020199 is an equidigital number, since it uses as much as digits as its factorization.

21001111020199 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 28.

The spelling of 21001111020199 in words is "twenty-one trillion, one billion, one hundred eleven million, twenty thousand, one hundred ninety-nine".