128260997 has 8 divisors (see below), whose sum is σ = 135921240. Its totient is φ = 120816640.

The previous prime is 128260991. The next prime is 128261009. The reversal of 128260997 is 799062821.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 25664356 + 102596641 = 5066^2 + 10129^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 128260997 - 2⁶ = 128260933 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128260991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52748 + ... + 55125.

It is an arithmetic number, because the mean of its divisors is an integer number (16990155).

Almost surely, 2^128260997 is an apocalyptic number.

It is an amenable number.

128260997 is a deficient number, since it is larger than the sum of its proper divisors (7660243).

128260997 is a wasteful number, since it uses less digits than its factorization.

128260997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107943.

The product of its (nonzero) digits is 108864, while the sum is 44.

The square root of 128260997 is about 11325.2371719095. The cubic root of 128260997 is about 504.3107245040.

The spelling of 128260997 in words is "one hundred twenty-eight million, two hundred sixty thousand, nine hundred ninety-seven".