1997838 has 16 divisors (see below), whose sum is σ = 4439760. Its totient is φ = 665928.

The previous prime is 1997833. The next prime is 1997843. The reversal of 1997838 is 8387991.

It is an interprime number because it is at equal distance from previous prime (1997833) and next prime (1997843).

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 1997793 and 1997802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1997833) 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, 18445 + ... + 18552.

It is an arithmetic number, because the mean of its divisors is an integer number (277485).

2^1997838 is an apocalyptic number.

1997838 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1997838 is an abundant number, since it is smaller than the sum of its proper divisors (2441922).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1997838 is a wasteful number, since it uses less digits than its factorization.

1997838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37008 (or 37002 counting only the distinct ones).

The product of its digits is 108864, while the sum is 45.

The square root of 1997838 is about 1413.4489732566. The cubic root of 1997838 is about 125.9466894657.

The spelling of 1997838 in words is "one million, nine hundred ninety-seven thousand, eight hundred thirty-eight".