21222340056506 has 16 divisors (see below), whose sum is σ = 32860575756288. Its totient is φ = 10268818518000.

The previous prime is 21222340056499. The next prime is 21222340056523. The reversal of 21222340056506 is 60565004322212.

It is a self number, because there is not a number n which added to its sum of digits gives 21222340056506.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12043556 + ... + 13692768.

It is an arithmetic number, because the mean of its divisors is an integer number (2053785984768).

Almost surely, 2^{21222340056506} is an apocalyptic number.

21222340056506 is a deficient number, since it is larger than the sum of its proper divisors (11638235699782).

21222340056506 is a wasteful number, since it uses less digits than its factorization.

21222340056506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1856797.

The product of its (nonzero) digits is 172800, while the sum is 38.

Adding to 21222340056506 its reverse (60565004322212), we get a palindrome (81787344378718).

The spelling of 21222340056506 in words is "twenty-one trillion, two hundred twenty-two billion, three hundred forty million, fifty-six thousand, five hundred six".