1997938 has 4 divisors (see below), whose sum is σ = 2996910. Its totient is φ = 998968.

The previous prime is 1997921. The next prime is 1997939. The reversal of 1997938 is 8397991.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1996569 + 1369 = 1413^2 + 37^2 .

It is not an unprimeable number, because it can be changed into a prime (1997939) 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 as a sum of consecutive naturals, namely, 499483 + ... + 499486.

2^1997938 is an apocalyptic number.

1997938 is a deficient number, since it is larger than the sum of its proper divisors (998972).

1997938 is an equidigital number, since it uses as much as digits as its factorization.

1997938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 998971.

The product of its digits is 122472, while the sum is 46.

The square root of 1997938 is about 1413.4843472780. The cubic root of 1997938 is about 125.9487908137.

The spelling of 1997938 in words is "one million, nine hundred ninety-seven thousand, nine hundred thirty-eight".