639342396 has 240 divisors, whose sum is σ = 2130374400. Its totient is φ = 165745440.

The previous prime is 639342377. The next prime is 639342469. The reversal of 639342396 is 693243936.

639342396 is a `hidden beast` number, since 639 + 3 + 4 + 2 + 3 + 9 + 6 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1222191 + ... + 1222713.

It is an arithmetic number, because the mean of its divisors is an integer number (8876560).

Almost surely, 2^639342396 is an apocalyptic number.

639342396 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 639342396, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1065187200).

639342396 is an abundant number, since it is smaller than the sum of its proper divisors (1491032004).

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

639342396 is a wasteful number, since it uses less digits than its factorization.

639342396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 571 (or 546 counting only the distinct ones).

The product of its digits is 629856, while the sum is 45.

The square root of 639342396 is about 25285.2209007554. The cubic root of 639342396 is about 861.4786155144.

The spelling of 639342396 in words is "six hundred thirty-nine million, three hundred forty-two thousand, three hundred ninety-six".