128981449 has 9 divisors (see below), whose sum is σ = 132683061. Its totient is φ = 125381280.

The previous prime is 128981429. The next prime is 128981453. The reversal of 128981449 is 944189821.

The square root of 128981449 is 11357.

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

It can be written as a sum of positive squares in 4 ways, for example, as 81812025 + 47169424 = 9045^2 + 6868^2 .

It is not a de Polignac number, because 128981449 - 2⁵ = 128981417 is a prime.

It is a super-2 number, since 2×128981449² = 33272428372279202, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 128981399 and 128981408.

It is not an unprimeable number, because it can be changed into a prime (128981429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 465499 + ... + 465775.

Almost surely, 2^128981449 is an apocalyptic number.

128981449 is the 11357-th square number.

128981449 is the 5679-th centered octagonal number.

It is an amenable number.

128981449 is a deficient number, since it is larger than the sum of its proper divisors (3701612).

128981449 is an frugal number, since it uses more digits than its factorization.

128981449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 636 (or 318 counting only the distinct ones).

The product of its digits is 165888, while the sum is 46.

The cubic root of 128981449 is about 505.2532128835.

The spelling of 128981449 in words is "one hundred twenty-eight million, nine hundred eighty-one thousand, four hundred forty-nine".