1811021530564 has 9 divisors (see below), whose sum is σ = 3169292388591. Its totient is φ = 905509419540.

The previous prime is 1811021530511. The next prime is 1811021530589. The reversal of 1811021530564 is 4650351201181.

The square root of 1811021530564 is 1345742.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 2355049 + ... + 3027919.

Almost surely, 2^{1811021530564} is an apocalyptic number.

1811021530564 is the 1345742-nd square number.

It is an amenable number.

1811021530564 is a deficient number, since it is larger than the sum of its proper divisors (1358270858027).

1811021530564 is an frugal number, since it uses more digits than its factorization.

1811021530564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1345746 (or 672873 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 37.

The spelling of 1811021530564 in words is "one trillion, eight hundred eleven billion, twenty-one million, five hundred thirty thousand, five hundred sixty-four".