77198561280 has 624 divisors, whose sum is σ = 288148109184. Its totient is φ = 19047383040.

The previous prime is 77198561273. The next prime is 77198561339. The reversal of 77198561280 is 8216589177.

77198561280 is a `hidden beast` number, since 7 + 7 + 19 + 8 + 5 + 612 + 8 + 0 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 222474067 + ... + 222474413.

It is an arithmetic number, because the mean of its divisors is an integer number (461775816).

Almost surely, 2^77198561280 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 77198561280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144074054592).

77198561280 is an abundant number, since it is smaller than the sum of its proper divisors (210949547904).

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

77198561280 is a wasteful number, since it uses less digits than its factorization.

77198561280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 470 (or 445 counting only the distinct ones).

The product of its (nonzero) digits is 1693440, while the sum is 54.

The spelling of 77198561280 in words is "seventy-seven billion, one hundred ninety-eight million, five hundred sixty-one thousand, two hundred eighty".