639788149 has 96 divisors (see below), whose sum is σ = 955608192. Its totient is φ = 419328000.

The previous prime is 639788141. The next prime is 639788161. The reversal of 639788149 is 941887936.

It is not a de Polignac number, because 639788149 - 2³ = 639788141 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 639788149.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639788141) 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 95 ways as a sum of consecutive naturals, for example, 4883814 + ... + 4883944.

It is an arithmetic number, because the mean of its divisors is an integer number (9954252).

Almost surely, 2^639788149 is an apocalyptic number.

It is an amenable number.

639788149 is a deficient number, since it is larger than the sum of its proper divisors (315820043).

639788149 is a wasteful number, since it uses less digits than its factorization.

639788149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227 (or 220 counting only the distinct ones).

The product of its digits is 2612736, while the sum is 55.

The square root of 639788149 is about 25294.0338617627. The cubic root of 639788149 is about 861.6787781974.

It can be divided in two parts, 63978 and 8149, that added together give a palindrome (72127).

The spelling of 639788149 in words is "six hundred thirty-nine million, seven hundred eighty-eight thousand, one hundred forty-nine".