128312819 has 2 divisors, whose sum is σ = 128312820. Its totient is φ = 128312818.

The previous prime is 128312783. The next prime is 128312831. The reversal of 128312819 is 918213821.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 128312819 - 2²⁴ = 111535603 is a prime.

It is a super-2 number, since 2×128312819² = 32928359039453522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (128312869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64156409 + 64156410.

It is an arithmetic number, because the mean of its divisors is an integer number (64156410).

Almost surely, 2^128312819 is an apocalyptic number.

128312819 is a deficient number, since it is larger than the sum of its proper divisors (1).

128312819 is an equidigital number, since it uses as much as digits as its factorization.

128312819 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6912, while the sum is 35.

The square root of 128312819 is about 11327.5248399639. The cubic root of 128312819 is about 504.3786351758.

The spelling of 128312819 in words is "one hundred twenty-eight million, three hundred twelve thousand, eight hundred nineteen".