20020121197 has 2 divisors, whose sum is σ = 20020121198. Its totient is φ = 20020121196.

The previous prime is 20020121171. The next prime is 20020121221. The reversal of 20020121197 is 79112102002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19475318916 + 544802281 = 139554^2 + 23341^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20020121197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20020121137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10010060598 + 10010060599.

It is an arithmetic number, because the mean of its divisors is an integer number (10010060599).

Almost surely, 2^20020121197 is an apocalyptic number.

It is an amenable number.

20020121197 is a deficient number, since it is larger than the sum of its proper divisors (1).

20020121197 is an equidigital number, since it uses as much as digits as its factorization.

20020121197 is an evil number, because the sum of its binary digits is even.

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

Adding to 20020121197 its reverse (79112102002), we get a palindrome (99132223199).

The spelling of 20020121197 in words is "twenty billion, twenty million, one hundred twenty-one thousand, one hundred ninety-seven".