20513363197 has 2 divisors, whose sum is σ = 20513363198. Its totient is φ = 20513363196.

The previous prime is 20513363161. The next prime is 20513363201. The reversal of 20513363197 is 79136331502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11939714361 + 8573648836 = 109269^2 + 92594^2 .

It is a cyclic number.

It is not a de Polignac number, because 20513363197 - 2¹⁵ = 20513330429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20513363107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10256681598 + 10256681599.

It is an arithmetic number, because the mean of its divisors is an integer number (10256681599).

Almost surely, 2^20513363197 is an apocalyptic number.

It is an amenable number.

20513363197 is a deficient number, since it is larger than the sum of its proper divisors (1).

20513363197 is an equidigital number, since it uses as much as digits as its factorization.

20513363197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 102060, while the sum is 40.

Adding to 20513363197 its reverse (79136331502), we get a palindrome (99649694699).

The spelling of 20513363197 in words is "twenty billion, five hundred thirteen million, three hundred sixty-three thousand, one hundred ninety-seven".