1802945 has 4 divisors (see below), whose sum is σ = 2163540. Its totient is φ = 1442352.

The previous prime is 1802923. The next prime is 1802989. The reversal of 1802945 is 5492081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5492081 = 7 ⋅784583.

It can be written as a sum of positive squares in 2 ways, for example, as 494209 + 1308736 = 703^2 + 1144^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1802945 is a prime.

It is a super-2 number, since 2×1802945² = 6501221346050, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 180290 + ... + 180299.

It is an arithmetic number, because the mean of its divisors is an integer number (540885).

2^1802945 is an apocalyptic number.

It is an amenable number.

1802945 is a deficient number, since it is larger than the sum of its proper divisors (360595).

1802945 is an equidigital number, since it uses as much as digits as its factorization.

1802945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360594.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 1802945 is about 1342.7378746427. The cubic root of 1802945 is about 121.7103448190.

It can be divided in two parts, 180 and 2945, that added together give a 5-th power (3125 = 5⁵).

The spelling of 1802945 in words is "one million, eight hundred two thousand, nine hundred forty-five".