1997973 has 8 divisors (see below), whose sum is σ = 2960000. Its totient is φ = 1331964.

The previous prime is 1997969. The next prime is 1997999. The reversal of 1997973 is 3797991.

It is not a de Polignac number, because 1997973 - 2² = 1997969 is a prime.

It is a super-2 number, since 2×1997973² = 7983792217458, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

1997973 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1997903) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 36973 + ... + 37026.

It is an arithmetic number, because the mean of its divisors is an integer number (370000).

2^1997973 is an apocalyptic number.

It is an amenable number.

1997973 is a deficient number, since it is larger than the sum of its proper divisors (962027).

1997973 is an equidigital number, since it uses as much as digits as its factorization.

1997973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74008 (or 74002 counting only the distinct ones).

The product of its digits is 107163, while the sum is 45.

The square root of 1997973 is about 1413.4967279764. The cubic root of 1997973 is about 125.9495262689.

The spelling of 1997973 in words is "one million, nine hundred ninety-seven thousand, nine hundred seventy-three".