21312213441 has 4 divisors (see below), whose sum is σ = 28416284592. Its totient is φ = 14208142292.

The previous prime is 21312213437. The next prime is 21312213449. The reversal of 21312213441 is 14431221312.

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 21312213441 - 2² = 21312213437 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21312213449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3552035571 + ... + 3552035576.

It is an arithmetic number, because the mean of its divisors is an integer number (7104071148).

Almost surely, 2^21312213441 is an apocalyptic number.

It is an amenable number.

21312213441 is a deficient number, since it is larger than the sum of its proper divisors (7104071151).

21312213441 is an equidigital number, since it uses as much as digits as its factorization.

21312213441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7104071150.

The product of its digits is 1152, while the sum is 24.

Adding to 21312213441 its reverse (14431221312), we get a palindrome (35743434753).

The spelling of 21312213441 in words is "twenty-one billion, three hundred twelve million, two hundred thirteen thousand, four hundred forty-one".