79991945280 has 588 divisors, whose sum is σ = 309401390340. Its totient is φ = 19680620544.

The previous prime is 79991945221. The next prime is 79991945287. The reversal of 79991945280 is 8254919997.

79991945280 is a `hidden beast` number, since 7 + 9 + 99 + 19 + 4 + 528 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 1021953024 + 78969992256 = 31968^2 + 281016^2 .

It is a super-2 number, since 2×79991945280² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79991945287) by changing a digit.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 39423306 + ... + 39425334.

Almost surely, 2^79991945280 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 79991945280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (154700695170).

79991945280 is an abundant number, since it is smaller than the sum of its proper divisors (229409445060).

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

79991945280 is a wasteful number, since it uses less digits than its factorization.

79991945280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2090 (or 2052 counting only the distinct ones).

The product of its (nonzero) digits is 14696640, while the sum is 63.

The spelling of 79991945280 in words is "seventy-nine billion, nine hundred ninety-one million, nine hundred forty-five thousand, two hundred eighty".