1997919 has 48 divisors (see below), whose sum is σ = 3813120. Its totient is φ = 1004400.

The previous prime is 1997911. The next prime is 1997921. The reversal of 1997919 is 9197991.

It is not a de Polignac number, because 1997919 - 2³ = 1997911 is a prime.

It is a super-2 number, since 2×1997919² = 7983360661122, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

1997919 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1997911) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 64434 + ... + 64464.

It is an arithmetic number, because the mean of its divisors is an integer number (79440).

2^1997919 is an apocalyptic number.

1997919 is a deficient number, since it is larger than the sum of its proper divisors (1815201).

1997919 is a wasteful number, since it uses less digits than its factorization.

1997919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89 (or 52 counting only the distinct ones).

The product of its digits is 45927, while the sum is 45.

The square root of 1997919 is about 1413.4776262821. The cubic root of 1997919 is about 125.9483915630.

It can be divided in two parts, 1997 and 919, that added together give a square (2916 = 54²).

The spelling of 1997919 in words is "one million, nine hundred ninety-seven thousand, nine hundred nineteen".