1997749 has 6 divisors (see below), whose sum is σ = 2163426. Its totient is φ = 1843920.

The previous prime is 1997747. The next prime is 1997753. The reversal of 1997749 is 9477991.

It can be written as a sum of positive squares in 3 ways, for example, as 79524 + 1918225 = 282^2 + 1385^2 .

It is not a de Polignac number, because 1997749 - 2¹ = 1997747 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1997699 and 1997708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1997747) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5742 + ... + 6079.

It is an arithmetic number, because the mean of its divisors is an integer number (360571).

2^1997749 is an apocalyptic number.

It is an amenable number.

1997749 is a deficient number, since it is larger than the sum of its proper divisors (165677).

1997749 is a wasteful number, since it uses less digits than its factorization.

1997749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11847 (or 11834 counting only the distinct ones).

The product of its digits is 142884, while the sum is 46.

The square root of 1997749 is about 1413.4174896328. The cubic root of 1997749 is about 125.9448192069.

The spelling of 1997749 in words is "one million, nine hundred ninety-seven thousand, seven hundred forty-nine".