999816725 has 6 divisors (see below), whose sum is σ = 1239772770. Its totient is φ = 799853360.

The previous prime is 999816721. The next prime is 999816737. The reversal of 999816725 is 527618999.

It can be written as a sum of positive squares in 3 ways, for example, as 168013444 + 831803281 = 12962^2 + 28841^2 .

It is not a de Polignac number, because 999816725 - 2² = 999816721 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999816721) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 19996310 + ... + 19996359.

It is an arithmetic number, because the mean of its divisors is an integer number (206628795).

Almost surely, 2^999816725 is an apocalyptic number.

It is an amenable number.

999816725 is a deficient number, since it is larger than the sum of its proper divisors (239956045).

999816725 is a wasteful number, since it uses less digits than its factorization.

999816725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39992679 (or 39992674 counting only the distinct ones).

The product of its digits is 2449440, while the sum is 56.

The square root of 999816725 is about 31619.8786367057. The cubic root of 999816725 is about 999.9389046008.

The spelling of 999816725 in words is "nine hundred ninety-nine million, eight hundred sixteen thousand, seven hundred twenty-five".