128990245 has 4 divisors (see below), whose sum is σ = 154788300. Its totient is φ = 103192192.

The previous prime is 128990227. The next prime is 128990269. The reversal of 128990245 is 542099821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 52969284 + 76020961 = 7278^2 + 8719^2 .

It is a cyclic number.

It is not a de Polignac number, because 128990245 - 2¹⁷ = 128859173 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 128990198 and 128990207.

It is a congruent number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 12899020 + ... + 12899029.

It is an arithmetic number, because the mean of its divisors is an integer number (38697075).

Almost surely, 2^128990245 is an apocalyptic number.

It is an amenable number.

128990245 is a deficient number, since it is larger than the sum of its proper divisors (25798055).

128990245 is an equidigital number, since it uses as much as digits as its factorization.

128990245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25798054.

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 128990245 is about 11357.3872435521. The cubic root of 128990245 is about 505.2646980138.

The spelling of 128990245 in words is "one hundred twenty-eight million, nine hundred ninety thousand, two hundred forty-five".