997776 has 90 divisors (see below), whose sum is σ = 3097458. Its totient is φ = 299520.

The previous prime is 997769. The next prime is 997783. The reversal of 997776 is 677799.

997776 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (997769) and next prime (997783).

It can be written as a sum of positive squares in 3 ways, for example, as 76176 + 921600 = 276^2 + 960^2 .

Its product of digits (166698) is a multiple of the sum of its prime factors (81).

It is a nialpdrome in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 24316 + ... + 24356.

2⁹⁹⁷⁷⁷⁶ 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 997776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1548729).

997776 is an abundant number, since it is smaller than the sum of its proper divisors (2099682).

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

997776 is a wasteful number, since it uses less digits than its factorization.

997776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81 (or 59 counting only the distinct ones).

The product of its digits is 166698, while the sum is 45.

The square root of 997776 is about 998.8873810395. The cubic root of 997776 is about 99.9258116412.

It can be divided in two parts, 99 and 7776, that added together give a triangular number (7875 = T₁₂₅).

The spelling of 997776 in words is "nine hundred ninety-seven thousand, seven hundred seventy-six".