6399308749 has 2 divisors, whose sum is σ = 6399308750. Its totient is φ = 6399308748.

The previous prime is 6399308743. The next prime is 6399308777. The reversal of 6399308749 is 9478039936.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6131986249 + 267322500 = 78307^2 + 16350^2 .

It is a cyclic number.

It is not a de Polignac number, because 6399308749 - 2¹⁹ = 6398784461 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6399308693 and 6399308702.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6399308743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3199654374 + 3199654375.

It is an arithmetic number, because the mean of its divisors is an integer number (3199654375).

Almost surely, 2^6399308749 is an apocalyptic number.

It is an amenable number.

6399308749 is a deficient number, since it is larger than the sum of its proper divisors (1).

6399308749 is an equidigital number, since it uses as much as digits as its factorization.

6399308749 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8817984, while the sum is 58.

The square root of 6399308749 is about 79995.6795645865. The cubic root of 6399308749 is about 1856.5686872275.

The spelling of 6399308749 in words is "six billion, three hundred ninety-nine million, three hundred eight thousand, seven hundred forty-nine".