129921217470 has 144 divisors (see below), whose sum is σ = 371779677360. Its totient is φ = 31454987520.

The previous prime is 129921217463. The next prime is 129921217493. The reversal of 129921217470 is 74712129921.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 8802637 + ... + 8817383.

It is an arithmetic number, because the mean of its divisors is an integer number (2581803315).

Almost surely, 2^129921217470 is an apocalyptic number.

129921217470 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 129921217470, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (185889838680).

129921217470 is an abundant number, since it is smaller than the sum of its proper divisors (241858459890).

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

129921217470 is a wasteful number, since it uses less digits than its factorization.

129921217470 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15591 (or 15577 counting only the distinct ones).

The product of its (nonzero) digits is 127008, while the sum is 45.

The spelling of 129921217470 in words is "one hundred twenty-nine billion, nine hundred twenty-one million, two hundred seventeen thousand, four hundred seventy".