1388091 has 4 divisors (see below), whose sum is σ = 1850792. Its totient is φ = 925392.

The previous prime is 1388081. The next prime is 1388113. The reversal of 1388091 is 1908831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1908831 = 3 ⋅636277.

It is not a de Polignac number, because 1388091 - 2⁵ = 1388059 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1388011) 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, 231346 + ... + 231351.

It is an arithmetic number, because the mean of its divisors is an integer number (462698).

2^1388091 is an apocalyptic number.

1388091 is a deficient number, since it is larger than the sum of its proper divisors (462701).

1388091 is an equidigital number, since it uses as much as digits as its factorization.

1388091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 462700.

The product of its (nonzero) digits is 1728, while the sum is 30.

The square root of 1388091 is about 1178.1727377596. The cubic root of 1388091 is about 111.5507889299.

The spelling of 1388091 in words is "one million, three hundred eighty-eight thousand, ninety-one".