128986646 has 4 divisors (see below), whose sum is σ = 193479972. Its totient is φ = 64493322.

The previous prime is 128986643. The next prime is 128986651. The reversal of 128986646 is 646689821.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 646689821 = 29 ⋅22299649.

It is a junction number, because it is equal to n+sod(n) for n = 128986594 and 128986603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128986643) 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 as a sum of consecutive naturals, namely, 32246660 + ... + 32246663.

It is an arithmetic number, because the mean of its divisors is an integer number (48369993).

Almost surely, 2^128986646 is an apocalyptic number.

128986646 is a deficient number, since it is larger than the sum of its proper divisors (64493326).

128986646 is an equidigital number, since it uses as much as digits as its factorization.

128986646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64493325.

The product of its digits is 995328, while the sum is 50.

The square root of 128986646 is about 11357.2287993154. The cubic root of 128986646 is about 505.2599987836.

The spelling of 128986646 in words is "one hundred twenty-eight million, nine hundred eighty-six thousand, six hundred forty-six".