129212550 has 48 divisors (see below), whose sum is σ = 356056080. Its totient is φ = 34456320.

The previous prime is 129212543. The next prime is 129212581. The reversal of 129212550 is 55212921.

129212550 is a `hidden beast` number, since 12 + 92 + 12 + 550 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 46507 + ... + 49206.

It is an arithmetic number, because the mean of its divisors is an integer number (7417835).

Almost surely, 2^129212550 is an apocalyptic number.

129212550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

129212550 is an abundant number, since it is smaller than the sum of its proper divisors (226843530).

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

129212550 is a wasteful number, since it uses less digits than its factorization.

129212550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95734 (or 95723 counting only the distinct ones).

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

The square root of 129212550 is about 11367.1698324605. The cubic root of 129212550 is about 505.5547933455.

The spelling of 129212550 in words is "one hundred twenty-nine million, two hundred twelve thousand, five hundred fifty".