39981267729 has 12 divisors (see below), whose sum is σ = 62193083316. Its totient is φ = 24603856992.

The previous prime is 39981267679. The next prime is 39981267749. The reversal of 39981267729 is 92776218993.

It can be written as a sum of positive squares in 2 ways, for example, as 3019282704 + 36961985025 = 54948^2 + 192255^2 .

It is not a de Polignac number, because 39981267729 - 2³³ = 31391333137 is a prime.

It is not an unprimeable number, because it can be changed into a prime (39981267749) 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 11 ways as a sum of consecutive naturals, for example, 170860002 + ... + 170860235.

It is an arithmetic number, because the mean of its divisors is an integer number (5182756943).

Almost surely, 2^39981267729 is an apocalyptic number.

39981267729 is a gapful number since it is divisible by the number (39) formed by its first and last digit.

It is an amenable number.

39981267729 is a deficient number, since it is larger than the sum of its proper divisors (22211815587).

39981267729 is a wasteful number, since it uses less digits than its factorization.

39981267729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341720256 (or 341720253 counting only the distinct ones).

The product of its digits is 20575296, while the sum is 63.

The spelling of 39981267729 in words is "thirty-nine billion, nine hundred eighty-one million, two hundred sixty-seven thousand, seven hundred twenty-nine".