128638706 has 8 divisors (see below), whose sum is σ = 220523520. Its totient is φ = 55130868.

The previous prime is 128638673. The next prime is 128638733. The reversal of 128638706 is 607836821.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4594226 + ... + 4594253.

It is an arithmetic number, because the mean of its divisors is an integer number (27565440).

Almost surely, 2^128638706 is an apocalyptic number.

128638706 is a deficient number, since it is larger than the sum of its proper divisors (91884814).

128638706 is an equidigital number, since it uses as much as digits as its factorization.

128638706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9188488.

The product of its (nonzero) digits is 96768, while the sum is 41.

The square root of 128638706 is about 11341.9004580361. The cubic root of 128638706 is about 504.8052786512.

The spelling of 128638706 in words is "one hundred twenty-eight million, six hundred thirty-eight thousand, seven hundred six".