128277869281 has 3 divisors (see below), whose sum is σ = 128278227441. Its totient is φ = 128277511122.

The previous prime is 128277869233. The next prime is 128277869311. The reversal of 128277869281 is 182968772821.

The square root of 128277869281 is 358159.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 182968772821 = 2393 ⋅76459997.

It is not a de Polignac number, because 128277869281 - 2¹¹ = 128277867233 is a prime.

It is a super-2 number, since 2×128277869281² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128277869081) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 179080 + ... + 537238.

It is an arithmetic number, because the mean of its divisors is an integer number (42759409147).

Almost surely, 2^128277869281 is an apocalyptic number.

128277869281 is the 358159-th square number.

128277869281 is the 179080-th centered octagonal number.

It is an amenable number.

128277869281 is a deficient number, since it is larger than the sum of its proper divisors (358160).

128277869281 is an frugal number, since it uses more digits than its factorization.

128277869281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 716318 (or 358159 counting only the distinct ones).

The product of its digits is 10838016, while the sum is 61.

The spelling of 128277869281 in words is "one hundred twenty-eight billion, two hundred seventy-seven million, eight hundred sixty-nine thousand, two hundred eighty-one".