77681237760 has 864 divisors, whose sum is σ = 329876090880. Its totient is φ = 16955744256.

The previous prime is 77681237747. The next prime is 77681237779. The reversal of 77681237760 is 6773218677.

It is a tau number, because it is divible by the number of its divisors (864).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 77681237697 and 77681237706.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 127975377 + ... + 127975983.

Almost surely, 2^77681237760 is an apocalyptic number.

77681237760 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77681237760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (164938045440).

77681237760 is an abundant number, since it is smaller than the sum of its proper divisors (252194853120).

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

77681237760 is a wasteful number, since it uses less digits than its factorization.

77681237760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690 (or 647 counting only the distinct ones).

The product of its (nonzero) digits is 4148928, while the sum is 54.

The spelling of 77681237760 in words is "seventy-seven billion, six hundred eighty-one million, two hundred thirty-seven thousand, seven hundred sixty".