2217178656 has 648 divisors, whose sum is σ = 8674074864. Its totient is φ = 550851840.

The previous prime is 2217178603. The next prime is 2217178657. The reversal of 2217178656 is 6568717122.

It is a tau number, because it is divible by the number of its divisors (648).

Its product of digits (282240) is a multiple of the sum of its prime factors (96).

It is not an unprimeable number, because it can be changed into a prime (2217178657) by changing a digit.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 96399061 + ... + 96399083.

It is an arithmetic number, because the mean of its divisors is an integer number (13385918).

Almost surely, 2^2217178656 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 2217178656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4337037432).

2217178656 is an abundant number, since it is smaller than the sum of its proper divisors (6456896208).

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

2217178656 is a wasteful number, since it uses less digits than its factorization.

2217178656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96 (or 46 counting only the distinct ones).

The product of its digits is 282240, while the sum is 45.

The square root of 2217178656 is about 47086.9265932700. The cubic root of 2217178656 is about 1303.9678878514.

The spelling of 2217178656 in words is "two billion, two hundred seventeen million, one hundred seventy-eight thousand, six hundred fifty-six".