9999725 has 6 divisors (see below), whose sum is σ = 12399690. Its totient is φ = 7999760.

The previous prime is 9999713. The next prime is 9999739. The reversal of 9999725 is 5279999.

9999725 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 1350244 + 8649481 = 1162^2 + 2941^2 .

It is not a de Polignac number, because 9999725 - 2⁸ = 9999469 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 199970 + ... + 200019.

It is an arithmetic number, because the mean of its divisors is an integer number (2066615).

Almost surely, 2^9999725 is an apocalyptic number.

It is an amenable number.

9999725 is a deficient number, since it is larger than the sum of its proper divisors (2399965).

9999725 is a wasteful number, since it uses less digits than its factorization.

9999725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399999 (or 399994 counting only the distinct ones).

The product of its digits is 459270, while the sum is 50.

The square root of 9999725 is about 3162.2341785516. The cubic root of 9999725 is about 215.4414940866.

The spelling of 9999725 in words is "nine million, nine hundred ninety-nine thousand, seven hundred twenty-five".