1645089 has 4 divisors (see below), whose sum is σ = 2193456. Its totient is φ = 1096724.

The previous prime is 1645087. The next prime is 1645093. The reversal of 1645089 is 9805461.

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, and also an emirpimes, since its reverse is a distinct semiprime: 9805461 = 3 ⋅3268487.

It is a cyclic number.

It is not a de Polignac number, because 1645089 - 2¹ = 1645087 is a prime.

It is a D-number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1645087) 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, 274179 + ... + 274184.

It is an arithmetic number, because the mean of its divisors is an integer number (548364).

2^1645089 is an apocalyptic number.

It is an amenable number.

1645089 is a deficient number, since it is larger than the sum of its proper divisors (548367).

1645089 is an equidigital number, since it uses as much as digits as its factorization.

1645089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548366.

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 1645089 is about 1282.6102291811. The cubic root of 1645089 is about 118.0492229765.

It can be divided in two parts, 164 and 5089, that added together give a triangular number (5253 = T₁₀₂).

The spelling of 1645089 in words is "one million, six hundred forty-five thousand, eighty-nine".