999557 has 8 divisors (see below), whose sum is σ = 1123584. Its totient is φ = 882288.

The previous prime is 999553. The next prime is 999563. The reversal of 999557 is 755999.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 999557 - 2² = 999553 is a prime.

It is a super-2 number, since 2×999557² = 1998228392498, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999553) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1373 + ... + 1970.

It is an arithmetic number, because the mean of its divisors is an integer number (140448).

2⁹⁹⁹⁵⁵⁷ is an apocalyptic number.

It is an amenable number.

999557 is a deficient number, since it is larger than the sum of its proper divisors (124027).

999557 is a wasteful number, since it uses less digits than its factorization.

999557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3379.

The product of its digits is 127575, while the sum is 44.

The square root of 999557 is about 999.7784754634. The cubic root of 999557 is about 99.9852311523.

The spelling of 999557 in words is "nine hundred ninety-nine thousand, five hundred fifty-seven".