1821544 has 8 divisors (see below), whose sum is σ = 3415410. Its totient is φ = 910768.

The previous prime is 1821541. The next prime is 1821551. The reversal of 1821544 is 4451281.

1821544 is nontrivially palindromic in base 5.

It can be written as a sum of positive squares in only one way, i.e., 1276900 + 544644 = 1130^2 + 738^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (1821541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 113839 + ... + 113854.

2^1821544 is an apocalyptic number.

It is an amenable number.

1821544 is a deficient number, since it is larger than the sum of its proper divisors (1593866).

1821544 is a wasteful number, since it uses less digits than its factorization.

1821544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 227699 (or 227695 counting only the distinct ones).

The product of its digits is 1280, while the sum is 25.

The square root of 1821544 is about 1349.6458794810. The cubic root of 1821544 is about 122.1274311245.

The spelling of 1821544 in words is "one million, eight hundred twenty-one thousand, five hundred forty-four".