9999557 has 4 divisors (see below), whose sum is σ = 10005996.
Its totient is φ = 9993120.
The previous prime is 9999533. The next prime is 9999593. The reversal of 9999557 is 7559999.
It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.
It can be written as a sum of positive squares in 2 ways, for example, as 9431041 + 568516 = 3071^2 + 754^2
It is a cyclic number.
It is not a de Polignac number, because 9999557 - 222 = 5805253 is a prime.
It is a super-2 number, since 2×99995572 = 199982280392498, which contains 22 as substring.
It is a Duffinian number.
It is a junction number, because it is equal to n+sod(n) for n = 9999499 and 9999508.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (9990557) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 707 + ... + 4527.
It is an arithmetic number, because the mean of its divisors is an integer number (2501499).
Almost surely, 29999557 is an apocalyptic number.
It is an amenable number.
9999557 is a deficient number, since it is larger than the sum of its proper divisors (6439).
9999557 is a wasteful number, since it uses less digits than its factorization.
9999557 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 6438.
The product of its digits is 1148175, while the sum is 53.
The square root of 9999557 is about 3162.2076149424.
The cubic root of 9999557 is about 215.4402875743.
The spelling of 9999557 in words is "nine million, nine hundred ninety-nine thousand, five hundred fifty-seven".