129551171040 has 768 divisors, whose sum is σ = 505564416000. Its totient is φ = 30831575040.

The previous prime is 129551171027. The next prime is 129551171137. The reversal of 129551171040 is 40171155921.

129551171040 is a `hidden beast` number, since 1 + 2 + 95 + 511 + 7 + 10 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 129551170986 and 129551171004.

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, 125655325 + ... + 125656355.

It is an arithmetic number, because the mean of its divisors is an integer number (658287000).

Almost surely, 2^129551171040 is an apocalyptic number.

129551171040 is a gapful number since it is divisible by the number (10) 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 129551171040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (252782208000).

129551171040 is an abundant number, since it is smaller than the sum of its proper divisors (376013244960).

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

129551171040 is a wasteful number, since it uses less digits than its factorization.

129551171040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1160 (or 1146 counting only the distinct ones).

The product of its (nonzero) digits is 12600, while the sum is 36.

The spelling of 129551171040 in words is "one hundred twenty-nine billion, five hundred fifty-one million, one hundred seventy-one thousand, forty".