21202222120991 has 2 divisors, whose sum is σ = 21202222120992. Its totient is φ = 21202222120990.

The previous prime is 21202222120969. The next prime is 21202222121029. The reversal of 21202222120991 is 19902122220212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21202222120991 - 2¹⁴ = 21202222104607 is a prime.

It is a super-3 number, since 3×21202222120991³ (a number of 41 digits) contains 333 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21202222120091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601111060495 + 10601111060496.

It is an arithmetic number, because the mean of its divisors is an integer number (10601111060496).

Almost surely, 2^{21202222120991} is an apocalyptic number.

21202222120991 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202222120991 is an equidigital number, since it uses as much as digits as its factorization.

21202222120991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 35.

The spelling of 21202222120991 in words is "twenty-one trillion, two hundred two billion, two hundred twenty-two million, one hundred twenty thousand, nine hundred ninety-one".