129156720 has 320 divisors, whose sum is σ = 518538240. Its totient is φ = 25804800.

The previous prime is 129156719. The next prime is 129156721. The reversal of 129156720 is 27651921.

It is an interprime number because it is at equal distance from previous prime (129156719) and next prime (129156721).

It is a super-3 number, since 3×129156720³ (a number of 25 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129156721) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 535800 + ... + 536040.

It is an arithmetic number, because the mean of its divisors is an integer number (1620432).

Almost surely, 2^129156720 is an apocalyptic number.

129156720 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 129156720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (259269120).

129156720 is an abundant number, since it is smaller than the sum of its proper divisors (389381520).

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

129156720 is a wasteful number, since it uses less digits than its factorization.

129156720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304 (or 298 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 33.

The square root of 129156720 is about 11364.7138107389. The cubic root of 129156720 is about 505.4819696911.

The spelling of 129156720 in words is "one hundred twenty-nine million, one hundred fifty-six thousand, seven hundred twenty".