21224213455 has 8 divisors (see below), whose sum is σ = 25637726304. Its totient is φ = 16866924000.

The previous prime is 21224213443. The next prime is 21224213459. The reversal of 21224213455 is 55431242212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21224213455 - 2²¹ = 21222116303 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21224213459) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14055016 + ... + 14056525.

It is an arithmetic number, because the mean of its divisors is an integer number (3204715788).

Almost surely, 2^21224213455 is an apocalyptic number.

21224213455 is a deficient number, since it is larger than the sum of its proper divisors (4413512849).

21224213455 is a wasteful number, since it uses less digits than its factorization.

21224213455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28111697.

The product of its digits is 19200, while the sum is 31.

Adding to 21224213455 its reverse (55431242212), we get a palindrome (76655455667).

The spelling of 21224213455 in words is "twenty-one billion, two hundred twenty-four million, two hundred thirteen thousand, four hundred fifty-five".