1997816 has 8 divisors (see below), whose sum is σ = 3745920. Its totient is φ = 998904.

The previous prime is 1997813. The next prime is 1997833. The reversal of 1997816 is 6187991.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent 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 as a sum of consecutive naturals, namely, 124856 + ... + 124871.

It is an arithmetic number, because the mean of its divisors is an integer number (468240).

2^1997816 is an apocalyptic number.

It is an amenable number.

1997816 is a deficient number, since it is larger than the sum of its proper divisors (1748104).

1997816 is a wasteful number, since it uses less digits than its factorization.

1997816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249733 (or 249729 counting only the distinct ones).

The product of its digits is 27216, while the sum is 41.

The square root of 1997816 is about 1413.4411908530. The cubic root of 1997816 is about 125.9462271597.

The spelling of 1997816 in words is "one million, nine hundred ninety-seven thousand, eight hundred sixteen".