21011109993719 has 2 divisors, whose sum is σ = 21011109993720. Its totient is φ = 21011109993718.

The previous prime is 21011109993689. The next prime is 21011109993739. The reversal of 21011109993719 is 91739990111012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21011109993719 - 2²⁰ = 21011108945143 is a prime.

It is a super-2 number, since 2×21011109993719² (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 (21011109993739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505554996859 + 10505554996860.

It is an arithmetic number, because the mean of its divisors is an integer number (10505554996860).

Almost surely, 2^{21011109993719} is an apocalyptic number.

21011109993719 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011109993719 is an equidigital number, since it uses as much as digits as its factorization.

21011109993719 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 275562, while the sum is 53.

The spelling of 21011109993719 in words is "twenty-one trillion, eleven billion, one hundred nine million, nine hundred ninety-three thousand, seven hundred nineteen".