78559921020 has 384 divisors, whose sum is σ = 268287344640. Its totient is φ = 16789893120.

The previous prime is 78559920883. The next prime is 78559921051. The reversal of 78559921020 is 2012995587.

It is a super-2 number, since 2×78559921020² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 86234365 + ... + 86235275.

It is an arithmetic number, because the mean of its divisors is an integer number (698664960).

Almost surely, 2^78559921020 is an apocalyptic number.

78559921020 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 78559921020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134143672320).

78559921020 is an abundant number, since it is smaller than the sum of its proper divisors (189727423620).

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

78559921020 is a wasteful number, since it uses less digits than its factorization.

78559921020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1145 (or 1143 counting only the distinct ones).

The product of its (nonzero) digits is 453600, while the sum is 48.

The spelling of 78559921020 in words is "seventy-eight billion, five hundred fifty-nine million, nine hundred twenty-one thousand, twenty".