1866040389 has 64 divisors (see below), whose sum is σ = 2903040000. Its totient is φ = 1183775040.

The previous prime is 1866040387. The next prime is 1866040399. The reversal of 1866040389 is 9830406681.

1866040389 is a `hidden beast` number, since 1 + 8 + 6 + 604 + 0 + 38 + 9 = 666.

It is not a de Polignac number, because 1866040389 - 2¹ = 1866040387 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1866040387) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 12523687 + ... + 12523835.

It is an arithmetic number, because the mean of its divisors is an integer number (45360000).

Almost surely, 2^1866040389 is an apocalyptic number.

It is an amenable number.

1866040389 is a deficient number, since it is larger than the sum of its proper divisors (1036999611).

1866040389 is a wasteful number, since it uses less digits than its factorization.

1866040389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 415 (or 409 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The square root of 1866040389 is about 43197.6896257196. The cubic root of 1866040389 is about 1231.1387847221.

It can be divided in two parts, 18660 and 40389, that added together give a 10-th power (59049 = 3¹⁰).

The spelling of 1866040389 in words is "one billion, eight hundred sixty-six million, forty thousand, three hundred eighty-nine".