1107991 has 4 divisors (see below), whose sum is σ = 1113984. Its totient is φ = 1102000.

The previous prime is 1107989. The next prime is 1108001. The reversal of 1107991 is 1997011.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1997011 = 439 ⋅4549.

It is a cyclic number.

It is not a de Polignac number, because 1107991 - 2¹ = 1107989 is a prime.

It is a Duffinian number.

1107991 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1107791) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2710 + ... + 3091.

It is an arithmetic number, because the mean of its divisors is an integer number (278496).

2^1107991 is an apocalyptic number.

1107991 is a deficient number, since it is larger than the sum of its proper divisors (5993).

1107991 is an equidigital number, since it uses as much as digits as its factorization.

1107991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5992.

The product of its (nonzero) digits is 567, while the sum is 28.

The square root of 1107991 is about 1052.6115142825. The cubic root of 1107991 is about 103.4773768690.

The spelling of 1107991 in words is "one million, one hundred seven thousand, nine hundred ninety-one".