1991474 has 4 divisors (see below), whose sum is σ = 2987214. Its totient is φ = 995736.

The previous prime is 1991461. The next prime is 1991477. The reversal of 1991474 is 4741991.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1117249 + 874225 = 1057^2 + 935^2 .

It is not an unprimeable number, because it can be changed into a prime (1991477) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 497867 + ... + 497870.

2^1991474 is an apocalyptic number.

1991474 is a deficient number, since it is larger than the sum of its proper divisors (995740).

1991474 is an equidigital number, since it uses as much as digits as its factorization.

1991474 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 995739.

The product of its digits is 9072, while the sum is 35.

The square root of 1991474 is about 1411.1959467062. The cubic root of 1991474 is about 125.8128151956.

The spelling of 1991474 in words is "one million, nine hundred ninety-one thousand, four hundred seventy-four".