1820660445 has 24 divisors (see below), whose sum is σ = 3186458496. Its totient is φ = 961589088.

The previous prime is 1820660437. The next prime is 1820660459. The reversal of 1820660445 is 5440660281.

1820660445 is a `hidden beast` number, since 1 + 8 + 2 + 0 + 6 + 604 + 45 = 666.

It is not a de Polignac number, because 1820660445 - 2³ = 1820660437 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 191769 + ... + 201038.

It is an arithmetic number, because the mean of its divisors is an integer number (132769104).

Almost surely, 2^1820660445 is an apocalyptic number.

1820660445 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1820660445 is a deficient number, since it is larger than the sum of its proper divisors (1365798051).

1820660445 is a wasteful number, since it uses less digits than its factorization.

1820660445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392921 (or 392918 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 1820660445 is about 42669.1978480965. The cubic root of 1820660445 is about 1221.0768162366.

The spelling of 1820660445 in words is "one billion, eight hundred twenty million, six hundred sixty thousand, four hundred forty-five".