642578199 has 16 divisors (see below), whose sum is σ = 905985024. Its totient is φ = 404452800.

The previous prime is 642578191. The next prime is 642578231. The reversal of 642578199 is 991875246.

It is not a de Polignac number, because 642578199 - 2³ = 642578191 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642578191) 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 15 ways as a sum of consecutive naturals, for example, 80449 + ... + 88074.

It is an arithmetic number, because the mean of its divisors is an integer number (56624064).

Almost surely, 2^642578199 is an apocalyptic number.

642578199 is a deficient number, since it is larger than the sum of its proper divisors (263406825).

642578199 is a wasteful number, since it uses less digits than its factorization.

642578199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168598.

The product of its digits is 1088640, while the sum is 51.

The square root of 642578199 is about 25349.1261979580. The cubic root of 642578199 is about 862.9295258627.

The spelling of 642578199 in words is "six hundred forty-two million, five hundred seventy-eight thousand, one hundred ninety-nine".