1997871 has 8 divisors (see below), whose sum is σ = 2683824. Its totient is φ = 1321920.

The previous prime is 1997867. The next prime is 1997887. The reversal of 1997871 is 1787991.

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 1997871 - 2² = 1997867 is a prime.

1997871 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1997851) 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, 2020 + ... + 2841.

It is an arithmetic number, because the mean of its divisors is an integer number (335478).

2^1997871 is an apocalyptic number.

1997871 is a deficient number, since it is larger than the sum of its proper divisors (685953).

1997871 is a wasteful number, since it uses less digits than its factorization.

1997871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5001.

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

The square root of 1997871 is about 1413.4606467815. The cubic root of 1997871 is about 125.9473829183.

The spelling of 1997871 in words is "one million, nine hundred ninety-seven thousand, eight hundred seventy-one".