128400019 has 8 divisors (see below), whose sum is σ = 140608512. Its totient is φ = 116280840.

The previous prime is 128400017. The next prime is 128400049. The reversal of 128400019 is 910004821.

It is a happy number.

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 128400019 - 2¹ = 128400017 is a prime.

It is a super-2 number, since 2×128400019² = 32973129758400722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 128399966 and 128400002.

It is not an unprimeable number, because it can be changed into a prime (128400011) 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, 19299 + ... + 25084.

It is an arithmetic number, because the mean of its divisors is an integer number (17576064).

Almost surely, 2^128400019 is an apocalyptic number.

128400019 is a deficient number, since it is larger than the sum of its proper divisors (12208493).

128400019 is a wasteful number, since it uses less digits than its factorization.

128400019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44657.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 128400019 is about 11331.3732177526. The cubic root of 128400019 is about 504.4928660529.

The spelling of 128400019 in words is "one hundred twenty-eight million, four hundred thousand, nineteen".