39987440640 has 1056 divisors, whose sum is σ = 171720046080. Its totient is φ = 8639447040.

The previous prime is 39987440587. The next prime is 39987440653. The reversal of 39987440640 is 4604478993.

It is a happy number.

39987440640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 929940459 + ... + 929940501.

It is an arithmetic number, because the mean of its divisors is an integer number (162613680).

Almost surely, 2^39987440640 is an apocalyptic number.

39987440640 is a gapful number since it is divisible by the number (30) 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 39987440640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85860023040).

39987440640 is an abundant number, since it is smaller than the sum of its proper divisors (131732605440).

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

39987440640 is a wasteful number, since it uses less digits than its factorization.

39987440640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146 (or 91 counting only the distinct ones).

The product of its (nonzero) digits is 5225472, while the sum is 54.

The spelling of 39987440640 in words is "thirty-nine billion, nine hundred eighty-seven million, four hundred forty thousand, six hundred forty".