1891089 has 12 divisors (see below), whose sum is σ = 2875600. Its totient is φ = 1194264.

The previous prime is 1891073. The next prime is 1891103. The reversal of 1891089 is 9801981.

It is not a de Polignac number, because 1891089 - 2⁴ = 1891073 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1891039) 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 11 ways as a sum of consecutive naturals, for example, 5359 + ... + 5700.

2^1891089 is an apocalyptic number.

1891089 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1891089 is a deficient number, since it is larger than the sum of its proper divisors (984511).

1891089 is a wasteful number, since it uses less digits than its factorization.

1891089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11084 (or 11081 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The square root of 1891089 is about 1375.1687169217. The cubic root of 1891089 is about 123.6623008883.

The spelling of 1891089 in words is "one million, eight hundred ninety-one thousand, eighty-nine".