129155400 has 216 divisors, whose sum is σ = 477567090. Its totient is φ = 31257600.

The previous prime is 129155363. The next prime is 129155401. The reversal of 129155400 is 4551921.

It can be written as a sum of positive squares in 3 ways, for example, as 101969604 + 27185796 = 10098^2 + 5214^2 .

It is a super-2 number, since 2×129155400² = 33362234698320000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129155401) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 217504 + ... + 218096.

Almost surely, 2^129155400 is an apocalyptic number.

129155400 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 129155400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (238783545).

129155400 is an abundant number, since it is smaller than the sum of its proper divisors (348411690).

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

129155400 is a wasteful number, since it uses less digits than its factorization.

129155400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 637 (or 614 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 27.

The square root of 129155400 is about 11364.6557360969. The cubic root of 129155400 is about 505.4802476528.

The spelling of 129155400 in words is "one hundred twenty-nine million, one hundred fifty-five thousand, four hundred".