128872769 has 2 divisors, whose sum is σ = 128872770. Its totient is φ = 128872768.

The previous prime is 128872753. The next prime is 128872811. The reversal of 128872769 is 967278821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 124032769 + 4840000 = 11137^2 + 2200^2 .

It is an emirp because it is prime and its reverse (967278821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 128872769 - 2⁴ = 128872753 is a prime.

It is a super-2 number, since 2×128872769² = 33216381179454722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (128872069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64436384 + 64436385.

It is an arithmetic number, because the mean of its divisors is an integer number (64436385).

Almost surely, 2^128872769 is an apocalyptic number.

It is an amenable number.

128872769 is a deficient number, since it is larger than the sum of its proper divisors (1).

128872769 is an equidigital number, since it uses as much as digits as its factorization.

128872769 is an evil number, because the sum of its binary digits is even.

The product of its digits is 677376, while the sum is 50.

The square root of 128872769 is about 11352.2142773998. The cubic root of 128872769 is about 505.1112639198. Note that the first 3 decimals are identical.

The spelling of 128872769 in words is "one hundred twenty-eight million, eight hundred seventy-two thousand, seven hundred sixty-nine".