997555 has 16 divisors (see below), whose sum is σ = 1310400. Its totient is φ = 724608.

The previous prime is 997553. The next prime is 997573. The reversal of 997555 is 555799.

It is a cyclic number.

It is not a de Polignac number, because 997555 - 2¹ = 997553 is a prime.

997555 is a lucky number.

It is a nialpdrome in base 10.

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 15 ways as a sum of consecutive naturals, for example, 6621 + ... + 6769.

It is an arithmetic number, because the mean of its divisors is an integer number (81900).

2⁹⁹⁷⁵⁵⁵ is an apocalyptic number.

997555 is a deficient number, since it is larger than the sum of its proper divisors (312845).

997555 is a wasteful number, since it uses less digits than its factorization.

997555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 270.

The product of its digits is 70875, while the sum is 40.

The square root of 997555 is about 998.7767518320. The cubic root of 997555 is about 99.9184334871.

The spelling of 997555 in words is "nine hundred ninety-seven thousand, five hundred fifty-five".