1809402 has 32 divisors (see below), whose sum is σ = 4204032. Its totient is φ = 508464.

The previous prime is 1809391. The next prime is 1809403. The reversal of 1809402 is 2049081.

It is not an unprimeable number, because it can be changed into a prime (1809403) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2493 + ... + 3135.

It is an arithmetic number, because the mean of its divisors is an integer number (131376).

2^1809402 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1809402, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2102016).

1809402 is an abundant number, since it is smaller than the sum of its proper divisors (2394630).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1809402 is a wasteful number, since it uses less digits than its factorization.

1809402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 722.

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 1809402 is about 1345.1401413979. The cubic root of 1809402 is about 121.8554680073.

It can be divided in two parts, 1809 and 402, that added together give a triangular number (2211 = T₆₆).

The spelling of 1809402 in words is "one million, eight hundred nine thousand, four hundred two".