77720772 has 48 divisors (see below), whose sum is σ = 189987840. Its totient is φ = 24681888.

The previous prime is 77720761. The next prime is 77720791. The reversal of 77720772 is 27702777.

It is a self number, because there is not a number n which added to its sum of digits gives 77720772.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 104233 + ... + 104975.

It is an arithmetic number, because the mean of its divisors is an integer number (3958080).

Almost surely, 2^77720772 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 77720772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94993920).

77720772 is an abundant number, since it is smaller than the sum of its proper divisors (112267068).

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

77720772 is a wasteful number, since it uses less digits than its factorization.

77720772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1152 (or 1150 counting only the distinct ones).

The product of its (nonzero) digits is 67228, while the sum is 39.

The square root of 77720772 is about 8815.9385206568. The cubic root of 77720772 is about 426.7554098720.

The spelling of 77720772 in words is "seventy-seven million, seven hundred twenty thousand, seven hundred seventy-two".