997568 has 56 divisors (see below), whose sum is σ = 2346960. Its totient is φ = 414720.

The previous prime is 997553. The next prime is 997573. The reversal of 997568 is 865799.

It is a Harshad number since it is a multiple of its sum of digits (44).

Its product of digits (136080) is a multiple of the sum of its prime divisors (135).

It is a zygodrome in base 2.

It is an unprimeable number.

997568 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9098 + ... + 9206.

It is an arithmetic number, because the mean of its divisors is an integer number (41910).

2⁹⁹⁷⁵⁶⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 997568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1173480).

997568 is an abundant number, since it is smaller than the sum of its proper divisors (1349392).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

997568 is a wasteful number, since it uses less digits than its factorization.

997568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145 (or 135 counting only the distinct ones).

The product of its digits is 136080, while the sum is 44.

The square root of 997568 is about 998.7832597716. The cubic root of 997568 is about 99.9188675264.

Subtracting from 997568 its reverse (865799), we obtain a square (131769 = 363²).

It can be divided in two parts, 99 and 7568, that added together give a palindrome (7667).

The spelling of 997568 in words is "nine hundred ninety-seven thousand, five hundred sixty-eight".