128005919 has 8 divisors (see below), whose sum is σ = 129606480. Its totient is φ = 126413056.

The previous prime is 128005873. The next prime is 128005921. The reversal of 128005919 is 919500821.

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 128005919 - 2⁸ = 128005663 is a prime.

It is a super-2 number, since 2×128005919² = 32771030598069122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128005949) 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, 36077 + ... + 39465.

It is an arithmetic number, because the mean of its divisors is an integer number (16200810).

Almost surely, 2^128005919 is an apocalyptic number.

128005919 is a deficient number, since it is larger than the sum of its proper divisors (1600561).

128005919 is a wasteful number, since it uses less digits than its factorization.

128005919 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3849.

The product of its (nonzero) digits is 6480, while the sum is 35.

The square root of 128005919 is about 11313.9700812756. The cubic root of 128005919 is about 503.9761880389.

The spelling of 128005919 in words is "one hundred twenty-eight million, five thousand, nine hundred nineteen".