221353606656 has 1400 divisors, whose sum is σ = 876934054920. Its totient is φ = 55306395648.

The previous prime is 221353606571. The next prime is 221353606667. The reversal of 221353606656 is 656606353122.

221353606656 is a `hidden beast` number, since 2 + 2 + 1 + 3 + 536 + 0 + 66 + 56 = 666.

221353606656 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a taxicab number since it can be written as a sum of two cubes in more than one way. Here 221353606656 = 504³ + 6048³ = 4536³ + 5040³.

It is a congruent number.

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 139 ways as a sum of consecutive naturals, for example, 11650189815 + ... + 11650189833.

Almost surely, 2^221353606656 is an apocalyptic number.

221353606656 is a gapful number since it is divisible by the number (26) 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 221353606656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (438467027460).

221353606656 is an abundant number, since it is smaller than the sum of its proper divisors (655580448264).

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

221353606656 is an frugal number, since it uses more digits than its factorization.

221353606656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96 (or 44 counting only the distinct ones).

The product of its (nonzero) digits is 1166400, while the sum is 45.

Adding to 221353606656 its reverse (656606353122), we get a palindrome (877959959778).

The spelling of 221353606656 in words is "two hundred twenty-one billion, three hundred fifty-three million, six hundred six thousand, six hundred fifty-six".