23128385281 has 4 divisors (see below), whose sum is σ = 23132660292. Its totient is φ = 23124110272.

The previous prime is 23128385251. The next prime is 23128385353. The reversal of 23128385281 is 18258382132.

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 2510010000 + 20618375281 = 50100^2 + 143591^2 .

It is a cyclic number.

It is not a de Polignac number, because 23128385281 - 2¹¹ = 23128383233 is a prime.

It is a super-2 number, since 2×23128385281² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23128385201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2129380 + ... + 2140213.

It is an arithmetic number, because the mean of its divisors is an integer number (5783165073).

Almost surely, 2^23128385281 is an apocalyptic number.

It is an amenable number.

23128385281 is a deficient number, since it is larger than the sum of its proper divisors (4275011).

23128385281 is an equidigital number, since it uses as much as digits as its factorization.

23128385281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4275010.

The product of its digits is 184320, while the sum is 43.

The spelling of 23128385281 in words is "twenty-three billion, one hundred twenty-eight million, three hundred eighty-five thousand, two hundred eighty-one".