3999972000049 has 3 divisors (see below), whose sum is σ = 3999974000043. Its totient is φ = 3999970000056.

The previous prime is 3999972000029. The next prime is 3999972000083. The reversal of 3999972000049 is 9400002799993.

The square root of 3999972000049 is 1999993.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 296779800625 + 3703192199424 = 544775^2 + 1924368^2 .

It is not a de Polignac number, because 3999972000049 - 2¹⁹ = 3999971475761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3999972000029) 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 2 ways as a sum of consecutive naturals, for example, 999997 + ... + 2999989.

It is an arithmetic number, because the mean of its divisors is an integer number (1333324666681).

Almost surely, 2^{3999972000049} is an apocalyptic number.

3999972000049 is the 1999993-rd square number.

3999972000049 is the 999997-th centered octagonal number.

It is an amenable number.

3999972000049 is a deficient number, since it is larger than the sum of its proper divisors (1999994).

3999972000049 is an frugal number, since it uses more digits than its factorization.

3999972000049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3999986 (or 1999993 counting only the distinct ones).

The product of its (nonzero) digits is 9920232, while the sum is 61.

The spelling of 3999972000049 in words is "three trillion, nine hundred ninety-nine billion, nine hundred seventy-two million, forty-nine", and thus it is an aban number.