1820025 has 18 divisors (see below), whose sum is σ = 3260270. Its totient is φ = 970560.

The previous prime is 1820023. The next prime is 1820033. The reversal of 1820025 is 5200281.

It can be written as a sum of positive squares in 3 ways, for example, as 13689 + 1806336 = 117^2 + 1344^2 .

It is not a de Polignac number, because 1820025 - 2¹ = 1820023 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1820023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 3820 + ... + 4269.

2^1820025 is an apocalyptic number.

1820025 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1820025 is a deficient number, since it is larger than the sum of its proper divisors (1440245).

1820025 is a wasteful number, since it uses less digits than its factorization.

1820025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8105 (or 8097 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 1820025 is about 1349.0830219078. The cubic root of 1820025 is about 122.0934740056.

It can be divided in two parts, 18200 and 25, that added together give a square (18225 = 135²).

The spelling of 1820025 in words is "one million, eight hundred twenty thousand, twenty-five".