639216732 has 192 divisors, whose sum is σ = 1950842880. Its totient is φ = 158092800.

The previous prime is 639216731. The next prime is 639216749. The reversal of 639216732 is 237612936.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639216731) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1780369 + ... + 1780727.

It is an arithmetic number, because the mean of its divisors is an integer number (10160640).

Almost surely, 2^639216732 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 639216732, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (975421440).

639216732 is an abundant number, since it is smaller than the sum of its proper divisors (1311626148).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

639216732 is a wasteful number, since it uses less digits than its factorization.

639216732 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 472 (or 470 counting only the distinct ones).

The product of its digits is 81648, while the sum is 39.

The square root of 639216732 is about 25282.7358487961. The cubic root of 639216732 is about 861.4221700464.

The spelling of 639216732 in words is "six hundred thirty-nine million, two hundred sixteen thousand, seven hundred thirty-two".