20211197 has 2 divisors, whose sum is σ = 20211198. Its totient is φ = 20211196.

The previous prime is 20211187. The next prime is 20211203. The reversal of 20211197 is 79111202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12432676 + 7778521 = 3526^2 + 2789^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20211197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20211127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105598 + 10105599.

It is an arithmetic number, because the mean of its divisors is an integer number (10105599).

Almost surely, 2^20211197 is an apocalyptic number.

It is an amenable number.

20211197 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211197 is an equidigital number, since it uses as much as digits as its factorization.

20211197 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 252, while the sum is 23.

The square root of 20211197 is about 4495.6864881795. The cubic root of 20211197 is about 272.3938795045.

Adding to 20211197 its reverse (79111202), we get a palindrome (99322399).

The spelling of 20211197 in words is "twenty million, two hundred eleven thousand, one hundred ninety-seven".