999993947 has 2 divisors, whose sum is σ = 999993948. Its totient is φ = 999993946.

The previous prime is 999993913. The next prime is 999993971. The reversal of 999993947 is 749399999.

It is a strong prime.

It is an emirp because it is prime and its reverse (749399999) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-999993947 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (999990947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499996973 + 499996974.

It is an arithmetic number, because the mean of its divisors is an integer number (499996974).

Almost surely, 2^999993947 is an apocalyptic number.

999993947 is a deficient number, since it is larger than the sum of its proper divisors (1).

999993947 is an equidigital number, since it uses as much as digits as its factorization.

999993947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 44641044, while the sum is 68.

The square root of 999993947 is about 31622.6808952056. The cubic root of 999993947 is about 999.9979823293.

The spelling of 999993947 in words is "nine hundred ninety-nine million, nine hundred ninety-three thousand, nine hundred forty-seven".