1921089 has 4 divisors (see below), whose sum is σ = 2561456. Its totient is φ = 1280724.

The previous prime is 1921079. The next prime is 1921097. The reversal of 1921089 is 9801291.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1921089 - 2¹¹ = 1919041 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 (1921069) 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, 320179 + ... + 320184.

It is an arithmetic number, because the mean of its divisors is an integer number (640364).

2^1921089 is an apocalyptic number.

It is an amenable number.

1921089 is a deficient number, since it is larger than the sum of its proper divisors (640367).

1921089 is an equidigital number, since it uses as much as digits as its factorization.

1921089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 640366.

The product of its (nonzero) digits is 1296, while the sum is 30.

The square root of 1921089 is about 1386.0335493775. The cubic root of 1921089 is about 124.3127942427.

The spelling of 1921089 in words is "one million, nine hundred twenty-one thousand, eighty-nine".