128869397 has 4 divisors (see below), whose sum is σ = 128892300. Its totient is φ = 128846496.

The previous prime is 128869379. The next prime is 128869399. The reversal of 128869397 is 793968821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 29149201 + 99720196 = 5399^2 + 9986^2 .

It is a cyclic number.

It is not a de Polignac number, because 128869397 - 2⁸ = 128869141 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 (128869399) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3473 + ... + 16425.

It is an arithmetic number, because the mean of its divisors is an integer number (32223075).

Almost surely, 2^128869397 is an apocalyptic number.

It is an amenable number.

128869397 is a deficient number, since it is larger than the sum of its proper divisors (22903).

128869397 is an equidigital number, since it uses as much as digits as its factorization.

128869397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22902.

The product of its digits is 1306368, while the sum is 53.

The square root of 128869397 is about 11352.0657591471. The cubic root of 128869397 is about 505.1068584118.

The spelling of 128869397 in words is "one hundred twenty-eight million, eight hundred sixty-nine thousand, three hundred ninety-seven".