6398998939 has 2 divisors, whose sum is σ = 6398998940. Its totient is φ = 6398998938.

The previous prime is 6398998919. The next prime is 6398998979. The reversal of 6398998939 is 9398998936.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6398998939 - 2⁷ = 6398998811 is a prime.

It is not a weakly prime, because it can be changed into another prime (6398998919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3199499469 + 3199499470.

It is an arithmetic number, because the mean of its divisors is an integer number (3199499470).

Almost surely, 2^6398998939 is an apocalyptic number.

6398998939 is a deficient number, since it is larger than the sum of its proper divisors (1).

6398998939 is an equidigital number, since it uses as much as digits as its factorization.

6398998939 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 204073344, while the sum is 73.

The square root of 6398998939 is about 79993.7431240719. The cubic root of 6398998939 is about 1856.5387260317.

The spelling of 6398998939 in words is "six billion, three hundred ninety-eight million, nine hundred ninety-eight thousand, nine hundred thirty-nine".