21000110012197 has 2 divisors, whose sum is σ = 21000110012198. Its totient is φ = 21000110012196.

The previous prime is 21000110012183. The next prime is 21000110012237. The reversal of 21000110012197 is 79121001100012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15535217292676 + 5464892719521 = 3941474^2 + 2337711^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000110012197 - 2¹¹ = 21000110010149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21000110010197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500055006098 + 10500055006099.

It is an arithmetic number, because the mean of its divisors is an integer number (10500055006099).

Almost surely, 2^{21000110012197} is an apocalyptic number.

It is an amenable number.

21000110012197 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000110012197 is an equidigital number, since it uses as much as digits as its factorization.

21000110012197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 252, while the sum is 25.

The spelling of 21000110012197 in words is "twenty-one trillion, one hundred ten million, twelve thousand, one hundred ninety-seven".