1997131 has 4 divisors (see below), whose sum is σ = 2004472. Its totient is φ = 1989792.

The previous prime is 1997129. The next prime is 1997137. The reversal of 1997131 is 1317991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1317991 = 131 ⋅10061.

It is a cyclic number.

It is not a de Polignac number, because 1997131 - 2¹ = 1997129 is a prime.

It is a super-2 number, since 2×1997131² = 7977064462322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1997093 and 1997102.

It is not an unprimeable number, because it can be changed into a prime (1997137) 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 3 ways as a sum of consecutive naturals, for example, 3246 + ... + 3811.

It is an arithmetic number, because the mean of its divisors is an integer number (501118).

2^1997131 is an apocalyptic number.

1997131 is a deficient number, since it is larger than the sum of its proper divisors (7341).

1997131 is an equidigital number, since it uses as much as digits as its factorization.

1997131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7340.

The product of its digits is 1701, while the sum is 31.

The square root of 1997131 is about 1413.1988536650. The cubic root of 1997131 is about 125.9318309344.

It can be divided in two parts, 19971 and 31, that added together give a palindrome (20002).

The spelling of 1997131 in words is "one million, nine hundred ninety-seven thousand, one hundred thirty-one".