1991300 has 18 divisors (see below), whose sum is σ = 4321338. Its totient is φ = 796480.

The previous prime is 1991293. The next prime is 1991351. The reversal of 1991300 is 31991.

It can be written as a sum of positive squares in 3 ways, for example, as 8836 + 1982464 = 94^2 + 1408^2 .

It is an Ulam number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9857 + ... + 10056.

2^1991300 is an apocalyptic number.

1991300 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1991300 is an abundant number, since it is smaller than the sum of its proper divisors (2330038).

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

1991300 is a wasteful number, since it uses less digits than its factorization.

1991300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19927 (or 19920 counting only the distinct ones).

The product of its (nonzero) digits is 243, while the sum is 23.

The square root of 1991300 is about 1411.1342955226. The cubic root of 1991300 is about 125.8091508968.

It can be divided in two parts, 19 and 91300, that added together give a palindrome (91319).

The spelling of 1991300 in words is "one million, nine hundred ninety-one thousand, three hundred".