6639696 has 90 divisors (see below), whose sum is σ = 21638682. Its totient is φ = 1895040.

The previous prime is 6639679. The next prime is 6639697. The reversal of 6639696 is 6969366.

6639696 is a `hidden beast` number, since 6 + 639 + 6 + 9 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 5934096 + 705600 = 2436^2 + 840^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6639697) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 6586 + ... + 7526.

Almost surely, 2^6639696 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 6639696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10819341).

6639696 is an abundant number, since it is smaller than the sum of its proper divisors (14998986).

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

6639696 is a wasteful number, since it uses less digits than its factorization.

6639696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 969 (or 953 counting only the distinct ones).

The product of its digits is 314928, while the sum is 45.

The square root of 6639696 is about 2576.7607572299. The cubic root of 6639696 is about 187.9530590516.

The spelling of 6639696 in words is "six million, six hundred thirty-nine thousand, six hundred ninety-six".