21216224015353 has 4 divisors (see below), whose sum is σ = 21236410718608. Its totient is φ = 21196037312100.

The previous prime is 21216224015339. The next prime is 21216224015383. The reversal of 21216224015353 is 35351042261212.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21216224015353 - 2⁴¹ = 19017200759801 is a prime.

It is a super-2 number, since 2×21216224015353² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21216224015383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10093350051 + ... + 10093352152.

It is an arithmetic number, because the mean of its divisors is an integer number (5309102679652).

Almost surely, 2^{21216224015353} is an apocalyptic number.

It is an amenable number.

21216224015353 is a deficient number, since it is larger than the sum of its proper divisors (20186703255).

21216224015353 is a wasteful number, since it uses less digits than its factorization.

21216224015353 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20186703254.

The product of its (nonzero) digits is 86400, while the sum is 37.

Adding to 21216224015353 its reverse (35351042261212), we get a palindrome (56567266276565).

The spelling of 21216224015353 in words is "twenty-one trillion, two hundred sixteen billion, two hundred twenty-four million, fifteen thousand, three hundred fifty-three".