9899947 has 2 divisors, whose sum is σ = 9899948. Its totient is φ = 9899946.

The previous prime is 9899921. The next prime is 9899951. The reversal of 9899947 is 7499989.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9899947 is a prime.

It is not a weakly prime, because it can be changed into another prime (9899977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4949973 + 4949974.

It is an arithmetic number, because the mean of its divisors is an integer number (4949974).

Almost surely, 2^9899947 is an apocalyptic number.

9899947 is a deficient number, since it is larger than the sum of its proper divisors (1).

9899947 is an equidigital number, since it uses as much as digits as its factorization.

9899947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1469664, while the sum is 55.

The square root of 9899947 is about 3146.4181222463. The cubic root of 9899947 is about 214.7225337256.

The spelling of 9899947 in words is "nine million, eight hundred ninety-nine thousand, nine hundred forty-seven".