128880391 has 2 divisors, whose sum is σ = 128880392. Its totient is φ = 128880390.

The previous prime is 128880341. The next prime is 128880419. The reversal of 128880391 is 193088821.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128880391 is a prime.

It is a super-2 number, since 2×128880391² = 33220310368625762, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128880341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64440195 + 64440196.

It is an arithmetic number, because the mean of its divisors is an integer number (64440196).

Almost surely, 2^128880391 is an apocalyptic number.

128880391 is a deficient number, since it is larger than the sum of its proper divisors (1).

128880391 is an equidigital number, since it uses as much as digits as its factorization.

128880391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27648, while the sum is 40.

The square root of 128880391 is about 11352.5499778684. The cubic root of 128880391 is about 505.1212217570.

The spelling of 128880391 in words is "one hundred twenty-eight million, eight hundred eighty thousand, three hundred ninety-one".