639853408911 has 4 divisors (see below), whose sum is σ = 853137878552. Its totient is φ = 426568939272.

The previous prime is 639853408897. The next prime is 639853408981. The reversal of 639853408911 is 119804358936.

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

It is not a de Polignac number, because 639853408911 - 2¹⁷ = 639853277839 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639853408981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 106642234816 + ... + 106642234821.

It is an arithmetic number, because the mean of its divisors is an integer number (213284469638).

Almost surely, 2^639853408911 is an apocalyptic number.

639853408911 is a deficient number, since it is larger than the sum of its proper divisors (213284469641).

639853408911 is a wasteful number, since it uses less digits than its factorization.

639853408911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213284469640.

The product of its (nonzero) digits is 5598720, while the sum is 57.

The spelling of 639853408911 in words is "six hundred thirty-nine billion, eight hundred fifty-three million, four hundred eight thousand, nine hundred eleven".