3999993209856 has 264 divisors, whose sum is σ = 13256580040704. Its totient is φ = 1137945968640.

The previous prime is 3999993209783. The next prime is 3999993209881. The reversal of 3999993209856 is 6589023999993.

3999993209856 is a `hidden beast` number, since 39 + 99 + 99 + 320 + 98 + 5 + 6 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14898241 + ... + 15164351.

It is an arithmetic number, because the mean of its divisors is an integer number (50214318336).

Almost surely, 2^{3999993209856} is an apocalyptic number.

3999993209856 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3999993209856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6628290020352).

3999993209856 is an abundant number, since it is smaller than the sum of its proper divisors (9256586830848).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3999993209856 is a wasteful number, since it uses less digits than its factorization.

3999993209856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266377 (or 266356 counting only the distinct ones).

The product of its (nonzero) digits is 2295825120, while the sum is 81.

The spelling of 3999993209856 in words is "three trillion, nine hundred ninety-nine billion, nine hundred ninety-three million, two hundred nine thousand, eight hundred fifty-six".