221565601629456 has 320 divisors, whose sum is σ = 664057822579200. Its totient is φ = 62350964932608.

The previous prime is 221565601629443. The next prime is 221565601629457. The reversal of 221565601629456 is 654926106565122.

It is a self number, because there is not a number n which added to its sum of digits gives 221565601629456.

It is not an unprimeable number, because it can be changed into a prime (221565601629457) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 25558376290 + ... + 25558384958.

It is an arithmetic number, because the mean of its divisors is an integer number (2075180695560).

Almost surely, 2^{221565601629456} 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 221565601629456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (332028911289600).

221565601629456 is an abundant number, since it is smaller than the sum of its proper divisors (442492220949744).

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

221565601629456 is a wasteful number, since it uses less digits than its factorization.

221565601629456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11986 (or 11980 counting only the distinct ones).

The product of its (nonzero) digits is 46656000, while the sum is 60.

The spelling of 221565601629456 in words is "two hundred twenty-one trillion, five hundred sixty-five billion, six hundred one million, six hundred twenty-nine thousand, four hundred fifty-six".