128445892261 has 4 divisors (see below), whose sum is σ = 135206202400. Its totient is φ = 121685582124.

The previous prime is 128445892247. The next prime is 128445892273. The reversal of 128445892261 is 162298544821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 162298544821 = 7 ⋅23185506403.

It is a cyclic number.

It is not a de Polignac number, because 128445892261 - 2²³ = 128437503653 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 128445892199 and 128445892208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128445892661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3380155041 + ... + 3380155078.

It is an arithmetic number, because the mean of its divisors is an integer number (33801550600).

Almost surely, 2^128445892261 is an apocalyptic number.

It is an amenable number.

128445892261 is a deficient number, since it is larger than the sum of its proper divisors (6760310139).

128445892261 is an equidigital number, since it uses as much as digits as its factorization.

128445892261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6760310138.

The product of its digits is 2211840, while the sum is 52.

The spelling of 128445892261 in words is "one hundred twenty-eight billion, four hundred forty-five million, eight hundred ninety-two thousand, two hundred sixty-one".