21011230016197 has 2 divisors, whose sum is σ = 21011230016198. Its totient is φ = 21011230016196.

The previous prime is 21011230016107. The next prime is 21011230016209. The reversal of 21011230016197 is 79161003211012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17372173984036 + 3639056032161 = 4167994^2 + 1907631^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21011230016197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21011230016107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505615008098 + 10505615008099.

It is an arithmetic number, because the mean of its divisors is an integer number (10505615008099).

Almost surely, 2^{21011230016197} is an apocalyptic number.

It is an amenable number.

21011230016197 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011230016197 is an equidigital number, since it uses as much as digits as its factorization.

21011230016197 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4536, while the sum is 34.

The spelling of 21011230016197 in words is "twenty-one trillion, eleven billion, two hundred thirty million, sixteen thousand, one hundred ninety-seven".