77903906820 has 96 divisors (see below), whose sum is σ = 221702116608. Its totient is φ = 20436836352.

The previous prime is 77903906789. The next prime is 77903906833. The reversal of 77903906820 is 2860930977.

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, 931864 + ... + 1012016.

It is an arithmetic number, because the mean of its divisors is an integer number (2309397048).

Almost surely, 2^77903906820 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 77903906820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110851058304).

77903906820 is an abundant number, since it is smaller than the sum of its proper divisors (143798209788).

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

77903906820 is a wasteful number, since it uses less digits than its factorization.

77903906820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80429 (or 80427 counting only the distinct ones).

The product of its (nonzero) digits is 1143072, while the sum is 51.

The spelling of 77903906820 in words is "seventy-seven billion, nine hundred three million, nine hundred six thousand, eight hundred twenty".