20399939257824 has 576 divisors, whose sum is σ = 71019486720000. Its totient is φ = 5544884782080.

The previous prime is 20399939257807. The next prime is 20399939257843. The reversal of 20399939257824 is 42875293999302.

20399939257824 is a `hidden beast` number, since 20 + 3 + 9 + 9 + 9 + 3 + 9 + 2 + 578 + 24 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 180619482 + ... + 180732390.

It is an arithmetic number, because the mean of its divisors is an integer number (123297720000).

Almost surely, 2^{20399939257824} is an apocalyptic number.

20399939257824 is a gapful number since it is divisible by the number (24) 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 20399939257824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35509743360000).

20399939257824 is an abundant number, since it is smaller than the sum of its proper divisors (50619547462176).

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

20399939257824 is a wasteful number, since it uses less digits than its factorization.

20399939257824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113036 (or 113011 counting only the distinct ones).

The product of its (nonzero) digits is 529079040, while the sum is 72.

The spelling of 20399939257824 in words is "twenty trillion, three hundred ninety-nine billion, nine hundred thirty-nine million, two hundred fifty-seven thousand, eight hundred twenty-four".