997180609 has 4 divisors (see below), whose sum is σ = 997263316. Its totient is φ = 997097904.

The previous prime is 997180589. The next prime is 997180643. The reversal of 997180609 is 906081799.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 506115009 + 491065600 = 22497^2 + 22160^2 .

It is a cyclic number.

It is not a de Polignac number, because 997180609 - 2¹¹ = 997178561 is a prime.

It is a super-2 number, since 2×997180609² = 1988738333931221762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (997180649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19374 + ... + 48679.

It is an arithmetic number, because the mean of its divisors is an integer number (249315829).

Almost surely, 2^997180609 is an apocalyptic number.

It is an amenable number.

997180609 is a deficient number, since it is larger than the sum of its proper divisors (82707).

997180609 is a wasteful number, since it uses less digits than its factorization.

997180609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82706.

The product of its (nonzero) digits is 244944, while the sum is 49.

The square root of 997180609 is about 31578.1666503931. The cubic root of 997180609 is about 999.0593183956.

The spelling of 997180609 in words is "nine hundred ninety-seven million, one hundred eighty thousand, six hundred nine".