129201840 has 120 divisors (see below), whose sum is σ = 436052448. Its totient is φ = 34283520.

The previous prime is 129201829. The next prime is 129201851. The reversal of 129201840 is 48102921.

It is an interprime number because it is at equal distance from previous prime (129201829) and next prime (129201851).

It is a tau number, because it is divible by the number of its divisors (120).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 223632 + ... + 224208.

Almost surely, 2^129201840 is an apocalyptic number.

129201840 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 129201840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (218026224).

129201840 is an abundant number, since it is smaller than the sum of its proper divisors (306850608).

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

129201840 is a wasteful number, since it uses less digits than its factorization.

129201840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 907 (or 898 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 129201840 is about 11366.6987291825. The cubic root of 129201840 is about 505.5408250392.

The spelling of 129201840 in words is "one hundred twenty-nine million, two hundred one thousand, eight hundred forty".