78122999808 has 672 divisors, whose sum is σ = 281336739840. Its totient is φ = 20384317440.

The previous prime is 78122999797. The next prime is 78122999831. The reversal of 78122999808 is 80899922187.

It is a tau number, because it is divible by the number of its divisors (672).

It is a super-2 number, since 2×78122999808² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 303980416 + ... + 303980672.

Almost surely, 2^78122999808 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 78122999808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140668369920).

78122999808 is an abundant number, since it is smaller than the sum of its proper divisors (203213740032).

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

78122999808 is a wasteful number, since it uses less digits than its factorization.

78122999808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 346 (or 319 counting only the distinct ones).

The product of its (nonzero) digits is 10450944, while the sum is 63.

The spelling of 78122999808 in words is "seventy-eight billion, one hundred twenty-two million, nine hundred ninety-nine thousand, eight hundred eight".