128993922 has 18 divisors (see below), whose sum is σ = 279591273. Its totient is φ = 42981912.

The previous prime is 128993911. The next prime is 128993923. The reversal of 128993922 is 229399821.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 81920601 + 47073321 = 9051^2 + 6861^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=8031.

It is not an unprimeable number, because it can be changed into a prime (128993923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 46848 + ... + 49524.

Almost surely, 2^128993922 is an apocalyptic number.

128993922 is an abundant number, since it is smaller than the sum of its proper divisors (150597351).

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

128993922 is an frugal number, since it uses more digits than its factorization.

128993922 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5362 (or 2682 counting only the distinct ones).

The product of its digits is 139968, while the sum is 45.

The square root of 128993922 is about 11357.5491194183. The cubic root of 128993922 is about 505.2694989987.

The spelling of 128993922 in words is "one hundred twenty-eight million, nine hundred ninety-three thousand, nine hundred twenty-two".