39999913 has 2 divisors, whose sum is σ = 39999914. Its totient is φ = 39999912.

The previous prime is 39999907. The next prime is 39999919. The reversal of 39999913 is 31999993.

It is a balanced prime because it is at equal distance from previous prime (39999907) and next prime (39999919).

It can be written as a sum of positive squares in only one way, i.e., 32398864 + 7601049 = 5692^2 + 2757^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-39999913 is a prime.

It is not a weakly prime, because it can be changed into another prime (39999919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19999956 + 19999957.

It is an arithmetic number, because the mean of its divisors is an integer number (19999957).

Almost surely, 2^39999913 is an apocalyptic number.

It is an amenable number.

39999913 is a deficient number, since it is larger than the sum of its proper divisors (1).

39999913 is an equidigital number, since it uses as much as digits as its factorization.

39999913 is an evil number, because the sum of its binary digits is even.

The product of its digits is 531441, while the sum is 52.

The square root of 39999913 is about 6324.5484423791. The cubic root of 39999913 is about 341.9949413886.

The spelling of 39999913 in words is "thirty-nine million, nine hundred ninety-nine thousand, nine hundred thirteen".