21214205304566 has 4 divisors (see below), whose sum is σ = 31821307956852. Its totient is φ = 10607102652282.

The previous prime is 21214205304527. The next prime is 21214205304569. The reversal of 21214205304566 is 66540350241212.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21214205304569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5303551326140 + ... + 5303551326143.

It is an arithmetic number, because the mean of its divisors is an integer number (7955326989213).

Almost surely, 2^{21214205304566} is an apocalyptic number.

21214205304566 is a deficient number, since it is larger than the sum of its proper divisors (10607102652286).

21214205304566 is a wasteful number, since it uses less digits than its factorization.

21214205304566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10607102652285.

The product of its (nonzero) digits is 345600, while the sum is 41.

Adding to 21214205304566 its reverse (66540350241212), we get a palindrome (87754555545778).

The spelling of 21214205304566 in words is "twenty-one trillion, two hundred fourteen billion, two hundred five million, three hundred four thousand, five hundred sixty-six".