21000201212197 has 2 divisors, whose sum is σ = 21000201212198. Its totient is φ = 21000201212196.

The previous prime is 21000201212117. The next prime is 21000201212213. The reversal of 21000201212197 is 79121210200012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14481784584036 + 6518416628161 = 3805494^2 + 2553119^2 .

It is a cyclic number.

It is not a de Polignac number, because 21000201212197 - 2¹⁵ = 21000201179429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21000201212117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500100606098 + 10500100606099.

It is an arithmetic number, because the mean of its divisors is an integer number (10500100606099).

Almost surely, 2^{21000201212197} is an apocalyptic number.

It is an amenable number.

21000201212197 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000201212197 is an equidigital number, since it uses as much as digits as its factorization.

21000201212197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 28.

The spelling of 21000201212197 in words is "twenty-one trillion, two hundred one million, two hundred twelve thousand, one hundred ninety-seven".