1809225 has 72 divisors (see below), whose sum is σ = 3830112. Its totient is φ = 806400.

The previous prime is 1809221. The next prime is 1809229. The reversal of 1809225 is 5229081.

It is an interprime number because it is at equal distance from previous prime (1809221) and next prime (1809229).

It is not a de Polignac number, because 1809225 - 2² = 1809221 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1809221) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 42054 + ... + 42096.

It is an arithmetic number, because the mean of its divisors is an integer number (53196).

2^1809225 is an apocalyptic number.

1809225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1809225 is an abundant number, since it is smaller than the sum of its proper divisors (2020887).

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

1809225 is a wasteful number, since it uses less digits than its factorization.

1809225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87 (or 79 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 1809225 is about 1345.0743473875. The cubic root of 1809225 is about 121.8514944807.

The spelling of 1809225 in words is "one million, eight hundred nine thousand, two hundred twenty-five".