129500400 has 120 divisors (see below), whose sum is σ = 417366144. Its totient is φ = 34323200.

The previous prime is 129500389. The next prime is 129500401. The reversal of 129500400 is 4005921.

129500400 = T₅₃₆₀ + T₅₃₆₁ + ... + T₅₃₆₈.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129500401) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 373027 + ... + 373373.

Almost surely, 2^129500400 is an apocalyptic number.

129500400 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 129500400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (208683072).

129500400 is an abundant number, since it is smaller than the sum of its proper divisors (287865744).

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

129500400 is a wasteful number, since it uses less digits than its factorization.

129500400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 679 (or 668 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 129500400 is about 11379.8242517185. The cubic root of 129500400 is about 505.9299272325.

The spelling of 129500400 in words is "one hundred twenty-nine million, five hundred thousand, four hundred".