128400199 has 4 divisors (see below), whose sum is σ = 128625640. Its totient is φ = 128174760.

The previous prime is 128400179. The next prime is 128400227. The reversal of 128400199 is 991004821.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 128400199 - 2¹⁹ = 127875911 is a prime.

It is a super-2 number, since 2×128400199² = 32973222206479202, 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 (128400179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111864 + ... + 113005.

It is an arithmetic number, because the mean of its divisors is an integer number (32156410).

Almost surely, 2^128400199 is an apocalyptic number.

128400199 is a deficient number, since it is larger than the sum of its proper divisors (225441).

128400199 is an equidigital number, since it uses as much as digits as its factorization.

128400199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225440.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 128400199 is about 11331.3811602999. The cubic root of 128400199 is about 504.4931017970.

The spelling of 128400199 in words is "one hundred twenty-eight million, four hundred thousand, one hundred ninety-nine".