21616622221354 has 4 divisors (see below), whose sum is σ = 32424933332034. Its totient is φ = 10808311110676.

The previous prime is 21616622221351. The next prime is 21616622221387. The reversal of 21616622221354 is 45312222661612.

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

It can be written as a sum of positive squares in only one way, i.e., 15115167679329 + 6501454542025 = 3887823^2 + 2549795^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21616622221354.

It is not an unprimeable number, because it can be changed into a prime (21616622221351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5404155555337 + ... + 5404155555340.

Almost surely, 2^{21616622221354} is an apocalyptic number.

21616622221354 is a deficient number, since it is larger than the sum of its proper divisors (10808311110680).

21616622221354 is a wasteful number, since it uses less digits than its factorization.

21616622221354 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10808311110679.

The product of its digits is 414720, while the sum is 43.

Adding to 21616622221354 its reverse (45312222661612), we get a palindrome (66928844882966).

The spelling of 21616622221354 in words is "twenty-one trillion, six hundred sixteen billion, six hundred twenty-two million, two hundred twenty-one thousand, three hundred fifty-four".