997557 has 32 divisors (see below), whose sum is σ = 1605120. Its totient is φ = 544320.

The previous prime is 997553. The next prime is 997573. The reversal of 997557 is 755799.

It is a happy number.

It is not a de Polignac number, because 997557 - 2² = 997553 is a prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 997557.

It is not an unprimeable number, because it can be changed into a prime (997553) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23178 + ... + 23220.

It is an arithmetic number, because the mean of its divisors is an integer number (50160).

2⁹⁹⁷⁵⁵⁷ is an apocalyptic number.

It is an amenable number.

997557 is a deficient number, since it is larger than the sum of its proper divisors (607563).

997557 is a wasteful number, since it uses less digits than its factorization.

997557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113.

The product of its digits is 99225, while the sum is 42.

The square root of 997557 is about 998.7777530562. Note that the first 4 decimals coincide. The cubic root of 997557 is about 99.9185002626.

The spelling of 997557 in words is "nine hundred ninety-seven thousand, five hundred fifty-seven".