20868198913 has 2 divisors, whose sum is σ = 20868198914. Its totient is φ = 20868198912.

The previous prime is 20868198877. The next prime is 20868198941. The reversal of 20868198913 is 31989186802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16245286849 + 4622912064 = 127457^2 + 67992^2 .

It is a cyclic number.

It is not a de Polignac number, because 20868198913 - 2⁹ = 20868198401 is a prime.

It is not a weakly prime, because it can be changed into another prime (20868198613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10434099456 + 10434099457.

It is an arithmetic number, because the mean of its divisors is an integer number (10434099457).

Almost surely, 2^20868198913 is an apocalyptic number.

It is an amenable number.

20868198913 is a deficient number, since it is larger than the sum of its proper divisors (1).

20868198913 is an equidigital number, since it uses as much as digits as its factorization.

20868198913 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1492992, while the sum is 55.

The spelling of 20868198913 in words is "twenty billion, eight hundred sixty-eight million, one hundred ninety-eight thousand, nine hundred thirteen".