1880391 has 4 divisors (see below), whose sum is σ = 2507192. Its totient is φ = 1253592.

The previous prime is 1880381. The next prime is 1880401. The reversal of 1880391 is 1930881.

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

It is an interprime number because it is at equal distance from previous prime (1880381) and next prime (1880401).

It is not a de Polignac number, because 1880391 - 2⁶ = 1880327 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1880321) 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, 313396 + ... + 313401.

It is an arithmetic number, because the mean of its divisors is an integer number (626798).

2^1880391 is an apocalyptic number.

1880391 is a deficient number, since it is larger than the sum of its proper divisors (626801).

1880391 is an equidigital number, since it uses as much as digits as its factorization.

1880391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626800.

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

The square root of 1880391 is about 1371.2734956966. The cubic root of 1880391 is about 123.4286715151.

The spelling of 1880391 in words is "one million, eight hundred eighty thousand, three hundred ninety-one".