21222000197 has 2 divisors, whose sum is σ = 21222000198. Its totient is φ = 21222000196.

The previous prime is 21222000139. The next prime is 21222000209. The reversal of 21222000197 is 79100022212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13289247841 + 7932752356 = 115279^2 + 89066^2 .

It is a cyclic number.

It is not a de Polignac number, because 21222000197 - 2⁸ = 21221999941 is a prime.

It is a super-2 number, since 2×21222000197² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21222000797) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611000098 + 10611000099.

It is an arithmetic number, because the mean of its divisors is an integer number (10611000099).

Almost surely, 2^21222000197 is an apocalyptic number.

It is an amenable number.

21222000197 is a deficient number, since it is larger than the sum of its proper divisors (1).

21222000197 is an equidigital number, since it uses as much as digits as its factorization.

21222000197 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 26.

The spelling of 21222000197 in words is "twenty-one billion, two hundred twenty-two million, one hundred ninety-seven", and thus it is an aban number.