639133899 has 4 divisors (see below), whose sum is σ = 852178536. Its totient is φ = 426089264.

The previous prime is 639133889. The next prime is 639133933. The reversal of 639133899 is 998331936.

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 639133899 - 2⁷ = 639133771 is a prime.

It is not an unprimeable number, because it can be changed into a prime (639133879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106522314 + ... + 106522319.

It is an arithmetic number, because the mean of its divisors is an integer number (213044634).

Almost surely, 2^639133899 is an apocalyptic number.

639133899 is a deficient number, since it is larger than the sum of its proper divisors (213044637).

639133899 is a wasteful number, since it uses less digits than its factorization.

639133899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213044636.

The product of its digits is 944784, while the sum is 51.

The square root of 639133899 is about 25281.0976620874. The cubic root of 639133899 is about 861.3849592636.

The spelling of 639133899 in words is "six hundred thirty-nine million, one hundred thirty-three thousand, eight hundred ninety-nine".