21201105926797 has 2 divisors, whose sum is σ = 21201105926798. Its totient is φ = 21201105926796.

The previous prime is 21201105926789. The next prime is 21201105926809. The reversal of 21201105926797 is 79762950110212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13548502127241 + 7652603799556 = 3680829^2 + 2766334^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201105926797 - 2³ = 21201105926789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21201105926717) 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, 10600552963398 + 10600552963399.

It is an arithmetic number, because the mean of its divisors is an integer number (10600552963399).

Almost surely, 2^{21201105926797} is an apocalyptic number.

It is an amenable number.

21201105926797 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201105926797 is an equidigital number, since it uses as much as digits as its factorization.

21201105926797 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 952560, while the sum is 52.

The spelling of 21201105926797 in words is "twenty-one trillion, two hundred one billion, one hundred five million, nine hundred twenty-six thousand, seven hundred ninety-seven".