19906863797 has 2 divisors, whose sum is σ = 19906863798. Its totient is φ = 19906863796.

The previous prime is 19906863731. The next prime is 19906863799. The reversal of 19906863797 is 79736860991.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17923586641 + 1983277156 = 133879^2 + 44534^2 .

It is a cyclic number.

It is not a de Polignac number, because 19906863797 - 2¹² = 19906859701 is a prime.

Together with 19906863799, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19906863799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9953431898 + 9953431899.

It is an arithmetic number, because the mean of its divisors is an integer number (9953431899).

Almost surely, 2^19906863797 is an apocalyptic number.

It is an amenable number.

19906863797 is a deficient number, since it is larger than the sum of its proper divisors (1).

19906863797 is an equidigital number, since it uses as much as digits as its factorization.

19906863797 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30862944, while the sum is 65.

The spelling of 19906863797 in words is "nineteen billion, nine hundred six million, eight hundred sixty-three thousand, seven hundred ninety-seven".