20396019989 has 2 divisors, whose sum is σ = 20396019990. Its totient is φ = 20396019988.

The previous prime is 20396019961. The next prime is 20396019997. The reversal of 20396019989 is 98991069302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19539287089 + 856732900 = 139783^2 + 29270^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20396019989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20396019289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10198009994 + 10198009995.

It is an arithmetic number, because the mean of its divisors is an integer number (10198009995).

Almost surely, 2^20396019989 is an apocalyptic number.

It is an amenable number.

20396019989 is a deficient number, since it is larger than the sum of its proper divisors (1).

20396019989 is an equidigital number, since it uses as much as digits as its factorization.

20396019989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1889568, while the sum is 56.

The spelling of 20396019989 in words is "twenty billion, three hundred ninety-six million, nineteen thousand, nine hundred eighty-nine".