129128777800 has 48 divisors (see below), whose sum is σ = 327517542000. Its totient is φ = 46955918400.

The previous prime is 129128777783. The next prime is 129128777809. The reversal of 129128777800 is 8777821921.

129128777800 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×129128777800² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (129128777809) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29345250 + ... + 29349649.

It is an arithmetic number, because the mean of its divisors is an integer number (6823282125).

Almost surely, 2^129128777800 is an apocalyptic number.

129128777800 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129128777800 is an abundant number, since it is smaller than the sum of its proper divisors (198388764200).

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

129128777800 is a wasteful number, since it uses less digits than its factorization.

129128777800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58694926 (or 58694917 counting only the distinct ones).

The product of its (nonzero) digits is 790272, while the sum is 52.

The spelling of 129128777800 in words is "one hundred twenty-nine billion, one hundred twenty-eight million, seven hundred seventy-seven thousand, eight hundred".