128506900 has 18 divisors (see below), whose sum is σ = 278860190. Its totient is φ = 51402720.

The previous prime is 128506891. The next prime is 128506907. The reversal of 128506900 is 9605821.

It can be written as a sum of positive squares in 3 ways, for example, as 2079364 + 126427536 = 1442^2 + 11244^2 .

It is a super-2 number, since 2×128506900² = 33028046695220000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128506907) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 642435 + ... + 642634.

Almost surely, 2^128506900 is an apocalyptic number.

128506900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128506900 is an abundant number, since it is smaller than the sum of its proper divisors (150353290).

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

128506900 is a wasteful number, since it uses less digits than its factorization.

128506900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1285083 (or 1285076 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 128506900 is about 11336.0883906222. The cubic root of 128506900 is about 504.6328082638.

The spelling of 128506900 in words is "one hundred twenty-eight million, five hundred six thousand, nine hundred".