128992506 has 16 divisors (see below), whose sum is σ = 260884800. Its totient is φ = 42514208.

The previous prime is 128992499. The next prime is 128992517. The reversal of 128992506 is 605299821.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 120246 + ... + 121313.

It is an arithmetic number, because the mean of its divisors is an integer number (16305300).

Almost surely, 2^128992506 is an apocalyptic number.

128992506 is an abundant number, since it is smaller than the sum of its proper divisors (131892294).

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

128992506 is a wasteful number, since it uses less digits than its factorization.

128992506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241653.

The product of its (nonzero) digits is 77760, while the sum is 42.

The square root of 128992506 is about 11357.4867818545. The cubic root of 128992506 is about 505.2676501668.

The spelling of 128992506 in words is "one hundred twenty-eight million, nine hundred ninety-two thousand, five hundred six".