39981999 has 16 divisors (see below), whose sum is σ = 54720000. Its totient is φ = 25958016.

The previous prime is 39981983. The next prime is 39982001. The reversal of 39981999 is 99918993.

39981999 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 39981999 - 2⁴ = 39981983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39981919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19002 + ... + 21000.

It is an arithmetic number, because the mean of its divisors is an integer number (3420000).

Almost surely, 2^39981999 is an apocalyptic number.

39981999 is a deficient number, since it is larger than the sum of its proper divisors (14738001).

39981999 is a wasteful number, since it uses less digits than its factorization.

39981999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2174.

The product of its digits is 1417176, while the sum is 57.

The square root of 39981999 is about 6323.1320561886. The cubic root of 39981999 is about 341.9438795093.

The spelling of 39981999 in words is "thirty-nine million, nine hundred eighty-one thousand, nine hundred ninety-nine".