1399091 has 4 divisors (see below), whose sum is σ = 1431672. Its totient is φ = 1366512.

The previous prime is 1399063. The next prime is 1399109. The reversal of 1399091 is 1909931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1909931 = 43 ⋅44417.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1399091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1399691) 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 in 3 ways as a sum of consecutive naturals, for example, 16226 + ... + 16311.

It is an arithmetic number, because the mean of its divisors is an integer number (357918).

2^1399091 is an apocalyptic number.

1399091 is a deficient number, since it is larger than the sum of its proper divisors (32581).

1399091 is an equidigital number, since it uses as much as digits as its factorization.

1399091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32580.

The product of its (nonzero) digits is 2187, while the sum is 32.

The square root of 1399091 is about 1182.8317716396. The cubic root of 1399091 is about 111.8446773412.

The spelling of 1399091 in words is "one million, three hundred ninety-nine thousand, ninety-one".