128991794453 has 2 divisors, whose sum is σ = 128991794454. Its totient is φ = 128991794452.

The previous prime is 128991794389. The next prime is 128991794461. The reversal of 128991794453 is 354497199821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 125604321649 + 3387472804 = 354407^2 + 58202^2 .

It is a cyclic number.

It is not a de Polignac number, because 128991794453 - 2⁶ = 128991794389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128991794483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64495897226 + 64495897227.

It is an arithmetic number, because the mean of its divisors is an integer number (64495897227).

Almost surely, 2^128991794453 is an apocalyptic number.

It is an amenable number.

128991794453 is a deficient number, since it is larger than the sum of its proper divisors (1).

128991794453 is an equidigital number, since it uses as much as digits as its factorization.

128991794453 is an evil number, because the sum of its binary digits is even.

The product of its digits is 19595520, while the sum is 62.

The spelling of 128991794453 in words is "one hundred twenty-eight billion, nine hundred ninety-one million, seven hundred ninety-four thousand, four hundred fifty-three".