1821272 has 16 divisors (see below), whose sum is σ = 3451560. Its totient is φ = 900864.

The previous prime is 1821263. The next prime is 1821289. The reversal of 1821272 is 2721281.

1821272 is a Rhonda number in base 9.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 398 + ... + 1949.

2^1821272 is an apocalyptic number.

It is an amenable number.

1821272 is a deficient number, since it is larger than the sum of its proper divisors (1630288).

1821272 is a wasteful number, since it uses less digits than its factorization.

1821272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2450 (or 2446 counting only the distinct ones).

The product of its digits is 448, while the sum is 23.

The square root of 1821272 is about 1349.5451085458. The cubic root of 1821272 is about 122.1213519750.

Subtracting 1821272 from its reverse (2721281), we obtain a palindrome (900009).

The spelling of 1821272 in words is "one million, eight hundred twenty-one thousand, two hundred seventy-two".