129777785856 has 264 divisors, whose sum is σ = 388773936720. Its totient is φ = 41646882816.

The previous prime is 129777785833. The next prime is 129777785911. The reversal of 129777785856 is 658587777921.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 164901495 + ... + 164902281.

Almost surely, 2^129777785856 is an apocalyptic number.

129777785856 is a gapful number since it is divisible by the number (16) 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 129777785856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (194386968360).

129777785856 is an abundant number, since it is smaller than the sum of its proper divisors (258996150864).

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

129777785856 is a wasteful number, since it uses less digits than its factorization.

129777785856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1459 (or 1438 counting only the distinct ones).

The product of its digits is 414892800, while the sum is 72.

The spelling of 129777785856 in words is "one hundred twenty-nine billion, seven hundred seventy-seven million, seven hundred eighty-five thousand, eight hundred fifty-six".