128922985 has 16 divisors (see below), whose sum is σ = 168239376. Its totient is φ = 94445568.

The previous prime is 128922979. The next prime is 128923001. The reversal of 128922985 is 589229821.

It can be written as a sum of positive squares in 8 ways, for example, as 1413721 + 127509264 = 1189^2 + 11292^2 .

It is a cyclic number.

It is not a de Polignac number, because 128922985 - 2²³ = 120534377 is a prime.

It is a super-2 number, since 2×128922985² = 33242272122620450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17352 + ... + 23641.

It is an arithmetic number, because the mean of its divisors is an integer number (10514961).

Almost surely, 2^128922985 is an apocalyptic number.

It is an amenable number.

128922985 is a deficient number, since it is larger than the sum of its proper divisors (39316391).

128922985 is a wasteful number, since it uses less digits than its factorization.

128922985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41052.

The product of its digits is 207360, while the sum is 46.

The square root of 128922985 is about 11354.4257890921. The cubic root of 128922985 is about 505.1768618829.

The spelling of 128922985 in words is "one hundred twenty-eight million, nine hundred twenty-two thousand, nine hundred eighty-five".