77798009520 has 960 divisors, whose sum is σ = 358059225600. Its totient is φ = 15310632960.

The previous prime is 77798009491. The next prime is 77798009537. The reversal of 77798009520 is 2590089777.

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

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 22118802 + ... + 22122318.

It is an arithmetic number, because the mean of its divisors is an integer number (372978360).

Almost surely, 2^77798009520 is an apocalyptic number.

77798009520 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 77798009520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179029612800).

77798009520 is an abundant number, since it is smaller than the sum of its proper divisors (280261216080).

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

77798009520 is a wasteful number, since it uses less digits than its factorization.

77798009520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3583 (or 3564 counting only the distinct ones).

The product of its (nonzero) digits is 2222640, while the sum is 54.

The spelling of 77798009520 in words is "seventy-seven billion, seven hundred ninety-eight million, nine thousand, five hundred twenty".