1997878 has 8 divisors (see below), whose sum is σ = 3013920. Its totient is φ = 993240.

The previous prime is 1997867. The next prime is 1997887. The reversal of 1997878 is 8787991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

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, 2398 + ... + 3121.

It is an arithmetic number, because the mean of its divisors is an integer number (376740).

2^1997878 is an apocalyptic number.

1997878 is a deficient number, since it is larger than the sum of its proper divisors (1016042).

1997878 is a wasteful number, since it uses less digits than its factorization.

1997878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5702.

The product of its digits is 254016, while the sum is 49.

The square root of 1997878 is about 1413.4631229714. The cubic root of 1997878 is about 125.9475300133.

The spelling of 1997878 in words is "one million, nine hundred ninety-seven thousand, eight hundred seventy-eight".