21620224166 has 8 divisors (see below), whose sum is σ = 33476476224. Its totient is φ = 10461398760.

The previous prime is 21620224141. The next prime is 21620224169. The reversal of 21620224166 is 66142202612.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21620224169) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 174356585 + ... + 174356708.

It is an arithmetic number, because the mean of its divisors is an integer number (4184559528).

Almost surely, 2^21620224166 is an apocalyptic number.

21620224166 is a deficient number, since it is larger than the sum of its proper divisors (11856252058).

21620224166 is a wasteful number, since it uses less digits than its factorization.

21620224166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 348713326.

The product of its (nonzero) digits is 13824, while the sum is 32.

Adding to 21620224166 its reverse (66142202612), we get a palindrome (87762426778).

The spelling of 21620224166 in words is "twenty-one billion, six hundred twenty million, two hundred twenty-four thousand, one hundred sixty-six".