639563829 has 8 divisors (see below), whose sum is σ = 889828032. Its totient is φ = 407837760.

The previous prime is 639563803. The next prime is 639563861. The reversal of 639563829 is 928365936.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-639563829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639563329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4634452 + ... + 4634589.

It is an arithmetic number, because the mean of its divisors is an integer number (111228504).

Almost surely, 2^639563829 is an apocalyptic number.

639563829 is a gapful number since it is divisible by the number (69) formed by its first and last digit.

It is an amenable number.

639563829 is a deficient number, since it is larger than the sum of its proper divisors (250264203).

639563829 is a wasteful number, since it uses less digits than its factorization.

639563829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9269067.

The product of its digits is 2099520, while the sum is 51.

The square root of 639563829 is about 25289.5992257687. The cubic root of 639563829 is about 861.5780602860.

The spelling of 639563829 in words is "six hundred thirty-nine million, five hundred sixty-three thousand, eight hundred twenty-nine".