39978694368 has 144 divisors (see below), whose sum is σ = 124835845680. Its totient is φ = 12542294016.

The previous prime is 39978694339. The next prime is 39978694391. The reversal of 39978694368 is 86349687993.

It is a tau number, because it is divible by the number of its divisors (144).

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

It is a junction number, because it is equal to n+sod(n) for n = 39978694296 and 39978694305.

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 23 ways as a sum of consecutive naturals, for example, 19023 + ... + 283406.

It is an arithmetic number, because the mean of its divisors is an integer number (866915595).

Almost surely, 2^39978694368 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 39978694368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (62417922840).

39978694368 is an abundant number, since it is smaller than the sum of its proper divisors (84857151312).

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

39978694368 is a wasteful number, since it uses less digits than its factorization.

39978694368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 302471 (or 302451 counting only the distinct ones).

The product of its digits is 423263232, while the sum is 72.

The spelling of 39978694368 in words is "thirty-nine billion, nine hundred seventy-eight million, six hundred ninety-four thousand, three hundred sixty-eight".