39966806889 has 45 divisors (see below), whose sum is σ = 60589926837. Its totient is φ = 26254699776.

The previous prime is 39966806881. The next prime is 39966806903. The reversal of 39966806889 is 98860866993.

The square root of 39966806889 is 199917.

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

It can be written as a sum of positive squares in 4 ways, for example, as 8173064025 + 31793742864 = 90405^2 + 178308^2 .

It is not a de Polignac number, because 39966806889 - 2³ = 39966806881 is a prime.

It is not an unprimeable number, because it can be changed into a prime (39966806881) by changing a digit.

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 44 ways as a sum of consecutive naturals, for example, 174527427 + ... + 174527655.

Almost surely, 2^39966806889 is an apocalyptic number.

39966806889 is the 199917-th square number.

39966806889 is the 99959-th centered octagonal number.

It is an amenable number.

39966806889 is a deficient number, since it is larger than the sum of its proper divisors (20623119948).

39966806889 is an frugal number, since it uses more digits than its factorization.

39966806889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 664 (or 329 counting only the distinct ones).

The product of its (nonzero) digits is 241864704, while the sum is 72.

The spelling of 39966806889 in words is "thirty-nine billion, nine hundred sixty-six million, eight hundred six thousand, eight hundred eighty-nine".