217428226560 has 1280 divisors, whose sum is σ = 868881530880. Its totient is φ = 51279298560.

The previous prime is 217428226559. The next prime is 217428226571. The reversal of 217428226560 is 65622824712.

217428226560 is a `hidden beast` number, since 2 + 1 + 7 + 4 + 2 + 82 + 2 + 6 + 560 = 666.

217428226560 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (1280).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1712033217 + ... + 1712033343.

It is an arithmetic number, because the mean of its divisors is an integer number (678813696).

Almost surely, 2^217428226560 is an apocalyptic number.

217428226560 is a gapful number since it is divisible by the number (20) 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 217428226560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (434440765440).

217428226560 is an abundant number, since it is smaller than the sum of its proper divisors (651453304320).

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

217428226560 is a wasteful number, since it uses less digits than its factorization.

217428226560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254 (or 232 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 45.

The spelling of 217428226560 in words is "two hundred seventeen billion, four hundred twenty-eight million, two hundred twenty-six thousand, five hundred sixty".