21102211021993 has 2 divisors, whose sum is σ = 21102211021994. Its totient is φ = 21102211021992.

The previous prime is 21102211021963. The next prime is 21102211022023. The reversal of 21102211021993 is 39912011220112.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (21102211021963) and next prime (21102211022023).

It can be written as a sum of positive squares in only one way, i.e., 18777766222224 + 2324444799769 = 4333332^2 + 1524613^2 .

It is a cyclic number.

It is not a de Polignac number, because 21102211021993 - 2²⁵ = 21102177467561 is a prime.

It is not a weakly prime, because it can be changed into another prime (21102211021933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10551105510996 + 10551105510997.

It is an arithmetic number, because the mean of its divisors is an integer number (10551105510997).

Almost surely, 2^{21102211021993} is an apocalyptic number.

It is an amenable number.

21102211021993 is a deficient number, since it is larger than the sum of its proper divisors (1).

21102211021993 is an equidigital number, since it uses as much as digits as its factorization.

21102211021993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 34.

The spelling of 21102211021993 in words is "twenty-one trillion, one hundred two billion, two hundred eleven million, twenty-one thousand, nine hundred ninety-three".