1866544985 has 8 divisors (see below), whose sum is σ = 2256952896. Its totient is φ = 1481836720.

The previous prime is 1866544969. The next prime is 1866544991. The reversal of 1866544985 is 5894456681.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1866544985 - 2⁴ = 1866544969 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1866544985.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1424189 + ... + 1425498.

It is an arithmetic number, because the mean of its divisors is an integer number (282119112).

Almost surely, 2^1866544985 is an apocalyptic number.

It is an amenable number.

1866544985 is a deficient number, since it is larger than the sum of its proper divisors (390407911).

1866544985 is a wasteful number, since it uses less digits than its factorization.

1866544985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2849823.

The product of its digits is 8294400, while the sum is 56.

The square root of 1866544985 is about 43203.5297747765. The cubic root of 1866544985 is about 1231.2497454714.

The spelling of 1866544985 in words is "one billion, eight hundred sixty-six million, five hundred forty-four thousand, nine hundred eighty-five".