216221606161 has 8 divisors (see below), whose sum is σ = 238528432800. Its totient is φ = 194356499040.

The previous prime is 216221606143. The next prime is 216221606171. The reversal of 216221606161 is 161606122612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-216221606161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216221606171) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 110428851 + ... + 110430808.

It is an arithmetic number, because the mean of its divisors is an integer number (29816054100).

Almost surely, 2^216221606161 is an apocalyptic number.

It is an amenable number.

216221606161 is a deficient number, since it is larger than the sum of its proper divisors (22306826639).

216221606161 is a wasteful number, since it uses less digits than its factorization.

216221606161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220859759.

The product of its (nonzero) digits is 10368, while the sum is 34.

Adding to 216221606161 its reverse (161606122612), we get a palindrome (377827728773).

The spelling of 216221606161 in words is "two hundred sixteen billion, two hundred twenty-one million, six hundred six thousand, one hundred sixty-one".