21221354344600 has 96 divisors (see below), whose sum is σ = 51625140779520. Its totient is φ = 8097350152320.

The previous prime is 21221354344591. The next prime is 21221354344609. The reversal of 21221354344600 is 644345312212.

It is an interprime number because it is at equal distance from previous prime (21221354344591) and next prime (21221354344609).

It is a self number, because there is not a number n which added to its sum of digits gives 21221354344600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221354344609) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4597002 + ... + 7973401.

It is an arithmetic number, because the mean of its divisors is an integer number (537761883120).

Almost surely, 2^{21221354344600} is an apocalyptic number.

21221354344600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221354344600 is an abundant number, since it is smaller than the sum of its proper divisors (30403786434920).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21221354344600 is a wasteful number, since it uses less digits than its factorization.

21221354344600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12570809 (or 12570800 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 37.

Adding to 21221354344600 its reverse (644345312212), we get a palindrome (21865699656812).

The spelling of 21221354344600 in words is "twenty-one trillion, two hundred twenty-one billion, three hundred fifty-four million, three hundred forty-four thousand, six hundred".