1997365 has 4 divisors (see below), whose sum is σ = 2396844. Its totient is φ = 1597888.

The previous prime is 1997351. The next prime is 1997407. The reversal of 1997365 is 5637991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5637991 = 1709 ⋅3299.

It can be written as a sum of positive squares in 2 ways, for example, as 1580049 + 417316 = 1257^2 + 646^2 .

It is a cyclic number.

It is not a de Polignac number, because 1997365 - 2¹¹ = 1995317 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

1997365 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 199732 + ... + 199741.

It is an arithmetic number, because the mean of its divisors is an integer number (599211).

2^1997365 is an apocalyptic number.

It is an amenable number.

1997365 is a deficient number, since it is larger than the sum of its proper divisors (399479).

1997365 is an equidigital number, since it uses as much as digits as its factorization.

1997365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 399478.

The product of its digits is 51030, while the sum is 40.

The square root of 1997365 is about 1413.2816421365. The cubic root of 1997365 is about 125.9367491391.

The spelling of 1997365 in words is "one million, nine hundred ninety-seven thousand, three hundred sixty-five".