21121110109999 has 2 divisors, whose sum is σ = 21121110110000. Its totient is φ = 21121110109998.

The previous prime is 21121110109963. The next prime is 21121110110003. The reversal of 21121110109999 is 99990101112112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21121110109999 - 2⁹ = 21121110109487 is a prime.

It is a super-2 number, since 2×21121110109999² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21121110109919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560555054999 + 10560555055000.

It is an arithmetic number, because the mean of its divisors is an integer number (10560555055000).

Almost surely, 2^{21121110109999} is an apocalyptic number.

21121110109999 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121110109999 is an equidigital number, since it uses as much as digits as its factorization.

21121110109999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26244, while the sum is 46.

The spelling of 21121110109999 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred ten million, one hundred nine thousand, nine hundred ninety-nine".