21220001197 has 2 divisors, whose sum is σ = 21220001198. Its totient is φ = 21220001196.

The previous prime is 21220001167. The next prime is 21220001213. The reversal of 21220001197 is 79110002212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14774159401 + 6445841796 = 121549^2 + 80286^2 .

It is a cyclic number.

It is not a de Polignac number, because 21220001197 - 2²⁷ = 21085783469 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21220001167) 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, 10610000598 + 10610000599.

It is an arithmetic number, because the mean of its divisors is an integer number (10610000599).

Almost surely, 2^21220001197 is an apocalyptic number.

It is an amenable number.

21220001197 is a deficient number, since it is larger than the sum of its proper divisors (1).

21220001197 is an equidigital number, since it uses as much as digits as its factorization.

21220001197 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 504, while the sum is 25.

The spelling of 21220001197 in words is "twenty-one billion, two hundred twenty million, one thousand, one hundred ninety-seven".