3217720128 has 112 divisors (see below), whose sum is σ = 9762134400. Its totient is φ = 916291584.

The previous prime is 3217720127. The next prime is 3217720141. The reversal of 3217720128 is 8210277123.

It is a tau number, because it is divible by the number of its divisors (112).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3217720127) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 416848 + ... + 424496.

Almost surely, 2^3217720128 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 3217720128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4881067200).

3217720128 is an abundant number, since it is smaller than the sum of its proper divisors (6544414272).

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

3217720128 is a wasteful number, since it uses less digits than its factorization.

3217720128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7984 (or 7974 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 33.

The square root of 3217720128 is about 56724.9515469163. The cubic root of 3217720128 is about 1476.3276569311.

The spelling of 3217720128 in words is "three billion, two hundred seventeen million, seven hundred twenty thousand, one hundred twenty-eight".