1997817 has 8 divisors (see below), whose sum is σ = 2670624. Its totient is φ = 1328448.

The previous prime is 1997813. The next prime is 1997833. The reversal of 1997817 is 7187991.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1997817 - 2² = 1997813 is a prime.

1997817 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1997813) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1218 + ... + 2340.

It is an arithmetic number, because the mean of its divisors is an integer number (333828).

2^1997817 is an apocalyptic number.

It is an amenable number.

1997817 is a deficient number, since it is larger than the sum of its proper divisors (672807).

1997817 is a wasteful number, since it uses less digits than its factorization.

1997817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1719.

The product of its digits is 31752, while the sum is 42.

The square root of 1997817 is about 1413.4415445996. The cubic root of 1997817 is about 125.9462481737.

The spelling of 1997817 in words is "one million, nine hundred ninety-seven thousand, eight hundred seventeen".