1681225 has 24 divisors (see below), whose sum is σ = 2569280. Its totient is φ = 1062720.

The previous prime is 1681219. The next prime is 1681241. The reversal of 1681225 is 5221861.

It is not a de Polignac number, because 1681225 - 2⁵ = 1681193 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

1681225 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1681225.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1906 + ... + 2644.

2^1681225 is an apocalyptic number.

It is an amenable number.

1681225 is a deficient number, since it is larger than the sum of its proper divisors (888055).

1681225 is a wasteful number, since it uses less digits than its factorization.

1681225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 769 (or 764 counting only the distinct ones).

The product of its digits is 960, while the sum is 25.

The square root of 1681225 is about 1296.6206075796. The cubic root of 1681225 is about 118.9073261003.

It can be divided in two parts, 1681 and 225, that multiplied together give a square (378225 = 615²).

The spelling of 1681225 in words is "one million, six hundred eighty-one thousand, two hundred twenty-five".