77420789280 has 192 divisors, whose sum is σ = 271107285120. Its totient is φ = 20635296768.

The previous prime is 77420789273. The next prime is 77420789291. The reversal of 77420789280 is 8298702477.

77420789280 is a `hidden beast` number, since 77 + 420 + 78 + 9 + 2 + 80 = 666.

It is a super-2 number, since 2×77420789280² (a number of 23 digits) contains 22 as substring.

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 31 ways as a sum of consecutive naturals, for example, 13315654 + ... + 13321466.

It is an arithmetic number, because the mean of its divisors is an integer number (1412017110).

Almost surely, 2^77420789280 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 77420789280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135553642560).

77420789280 is an abundant number, since it is smaller than the sum of its proper divisors (193686495840).

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

77420789280 is a wasteful number, since it uses less digits than its factorization.

77420789280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8920 (or 8906 counting only the distinct ones).

The product of its (nonzero) digits is 3161088, while the sum is 54.

The spelling of 77420789280 in words is "seventy-seven billion, four hundred twenty million, seven hundred eighty-nine thousand, two hundred eighty".