997771 has 4 divisors (see below), whose sum is σ = 1005192. Its totient is φ = 990352.

The previous prime is 997769. The next prime is 997783. The reversal of 997771 is 177799.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 177799 = 29 ⋅6131.

It is a cyclic number.

It is not a de Polignac number, because 997771 - 2¹ = 997769 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (997741) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3505 + ... + 3778.

It is an arithmetic number, because the mean of its divisors is an integer number (251298).

2⁹⁹⁷⁷⁷¹ is an apocalyptic number.

997771 is a deficient number, since it is larger than the sum of its proper divisors (7421).

997771 is a wasteful number, since it uses less digits than its factorization.

997771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7420.

The product of its digits is 27783, while the sum is 40.

The square root of 997771 is about 998.8848782517. The cubic root of 997771 is about 99.9256447266.

The spelling of 997771 in words is "nine hundred ninety-seven thousand, seven hundred seventy-one".