77780000 has 60 divisors (see below), whose sum is σ = 191399670. Its totient is φ = 31104000.

The previous prime is 77779987. The next prime is 77780009. The reversal of 77780000 is 8777.

It can be written as a sum of positive squares in 5 ways, for example, as 3888784 + 73891216 = 1972^2 + 8596^2 .

It is not an unprimeable number, because it can be changed into a prime (77780009) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 18056 + ... + 21944.

Almost surely, 2^77780000 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 77780000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95699835).

77780000 is an abundant number, since it is smaller than the sum of its proper divisors (113619670).

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

77780000 is an equidigital number, since it uses as much as digits as its factorization.

77780000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3919 (or 3896 counting only the distinct ones).

The product of its (nonzero) digits is 2744, while the sum is 29.

The square root of 77780000 is about 8819.2970241397. The cubic root of 77780000 is about 426.8637869545.

Adding to 77780000 its reverse (8777), we get a palindrome (77788777).

The spelling of 77780000 in words is "seventy-seven million, seven hundred eighty thousand".