129256550340 has 96 divisors (see below), whose sum is σ = 373749175296. Its totient is φ = 33342597120.

The previous prime is 129256550317. The next prime is 129256550359. The reversal of 129256550340 is 43055652921.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 129256550292 and 129256550301.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4884184 + ... + 4910576.

It is an arithmetic number, because the mean of its divisors is an integer number (3893220576).

Almost surely, 2^129256550340 is an apocalyptic number.

129256550340 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 129256550340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (186874587648).

129256550340 is an abundant number, since it is smaller than the sum of its proper divisors (244492624956).

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

129256550340 is a wasteful number, since it uses less digits than its factorization.

129256550340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29069 (or 29067 counting only the distinct ones).

The product of its (nonzero) digits is 324000, while the sum is 42.

The spelling of 129256550340 in words is "one hundred twenty-nine billion, two hundred fifty-six million, five hundred fifty thousand, three hundred forty".