128244920769 has 27 divisors (see below), whose sum is σ = 215499000483. Its totient is φ = 73278514512.

The previous prime is 128244920717. The next prime is 128244920789. The reversal of 128244920769 is 967029442821.

It is a happy number.

The square root of 128244920769 is 358113.

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

128244920769 is a `hidden beast` number, since 1 + 2 + 82 + 4 + 492 + 0 + 76 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 47013080625 + 81231840144 = 216825^2 + 285012^2 .

It is not a de Polignac number, because 128244920769 - 2⁷ = 128244920641 is a prime.

It is a super-2 number, since 2×128244920769² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (128244920789) 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 26 ways as a sum of consecutive naturals, for example, 7511847 + ... + 7528899.

Almost surely, 2^128244920769 is an apocalyptic number.

128244920769 is the 358113-rd square number.

128244920769 is the 179057-th centered octagonal number.

It is an amenable number.

128244920769 is a deficient number, since it is larger than the sum of its proper divisors (87254079714).

128244920769 is an frugal number, since it uses more digits than its factorization.

128244920769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34126 (or 17063 counting only the distinct ones).

The product of its (nonzero) digits is 3483648, while the sum is 54.

The spelling of 128244920769 in words is "one hundred twenty-eight billion, two hundred forty-four million, nine hundred twenty thousand, seven hundred sixty-nine".