129651228 has 144 divisors (see below), whose sum is σ = 393382080. Its totient is φ = 35223552.

The previous prime is 129651211. The next prime is 129651233. The reversal of 129651228 is 822156921.

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 = 129651192 and 129651201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 825726 + ... + 825882.

It is an arithmetic number, because the mean of its divisors is an integer number (2731820).

Almost surely, 2^129651228 is an apocalyptic number.

129651228 is a gapful number since it is divisible by the number (18) 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 129651228, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (196691040).

129651228 is an abundant number, since it is smaller than the sum of its proper divisors (263730852).

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

129651228 is a wasteful number, since it uses less digits than its factorization.

129651228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316 (or 311 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 129651228 is about 11386.4493148655. The cubic root of 129651228 is about 506.1262684355.

The spelling of 129651228 in words is "one hundred twenty-nine million, six hundred fifty-one thousand, two hundred twenty-eight".