77761800000 has 252 divisors, whose sum is σ = 278601316812. Its totient is φ = 20736000000.

The previous prime is 77761799971. The next prime is 77761800041. The reversal of 77761800000 is 816777.

It can be written as a sum of positive squares in 6 ways, for example, as 57853718784 + 19908081216 = 240528^2 + 141096^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1778400 + ... + 1821600.

It is an arithmetic number, because the mean of its divisors is an integer number (1105560781).

Almost surely, 2^77761800000 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 77761800000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (139300658406).

77761800000 is an abundant number, since it is smaller than the sum of its proper divisors (200839516812).

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

77761800000 is an equidigital number, since it uses as much as digits as its factorization.

77761800000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43244 (or 43211 counting only the distinct ones).

The product of its (nonzero) digits is 16464, while the sum is 36.

The spelling of 77761800000 in words is "seventy-seven billion, seven hundred sixty-one million, eight hundred thousand".