8139942720 has 1680 divisors, whose sum is σ = 39731685840. Its totient is φ = 1560674304.

The previous prime is 8139942689. The next prime is 8139942743. The reversal of 8139942720 is 272499318.

It can be written as a sum of positive squares in 8 ways, for example, as 91699776 + 8048242944 = 9576^2 + 89712^2 .

It is a tau number, because it is divible by the number of its divisors (1680).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 280687666 + ... + 280687694.

It is an arithmetic number, because the mean of its divisors is an integer number (23649813).

Almost surely, 2^8139942720 is an apocalyptic number.

8139942720 is a gapful number since it is divisible by the number (80) 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 8139942720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19865842920).

8139942720 is an abundant number, since it is smaller than the sum of its proper divisors (31591743120).

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

8139942720 is a wasteful number, since it uses less digits than its factorization.

8139942720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102 (or 76 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The square root of 8139942720 is about 90221.6311091747. The cubic root of 8139942720 is about 2011.5945466856.

The spelling of 8139942720 in words is "eight billion, one hundred thirty-nine million, nine hundred forty-two thousand, seven hundred twenty".