21234201166 has 4 divisors (see below), whose sum is σ = 31851301752. Its totient is φ = 10617100582.

The previous prime is 21234201139. The next prime is 21234201187. The reversal of 21234201166 is 66110243212.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5308550290 + ... + 5308550293.

It is an arithmetic number, because the mean of its divisors is an integer number (7962825438).

Almost surely, 2^21234201166 is an apocalyptic number.

21234201166 is a deficient number, since it is larger than the sum of its proper divisors (10617100586).

21234201166 is a wasteful number, since it uses less digits than its factorization.

21234201166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10617100585.

The product of its (nonzero) digits is 3456, while the sum is 28.

Adding to 21234201166 its reverse (66110243212), we get a palindrome (87344444378).

The spelling of 21234201166 in words is "twenty-one billion, two hundred thirty-four million, two hundred one thousand, one hundred sixty-six".