1809420 has 48 divisors (see below), whose sum is σ = 5171040. Its totient is φ = 472576.

The previous prime is 1809419. The next prime is 1809421. The reversal of 1809420 is 249081.

It is an interprime number because it is at equal distance from previous prime (1809419) and next prime (1809421).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1809421) 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, 2896 + ... + 3464.

It is an arithmetic number, because the mean of its divisors is an integer number (107730).

2^1809420 is an apocalyptic number.

1809420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1809420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2585520).

1809420 is an abundant number, since it is smaller than the sum of its proper divisors (3361620).

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

1809420 is a wasteful number, since it uses less digits than its factorization.

1809420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 634 (or 632 counting only the distinct ones).

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

The square root of 1809420 is about 1345.1468321339. The cubic root of 1809420 is about 121.8558720803.

The spelling of 1809420 in words is "one million, eight hundred nine thousand, four hundred twenty".