21344441413 has 4 divisors (see below), whose sum is σ = 21345117868. Its totient is φ = 21343764960.

The previous prime is 21344441383. The next prime is 21344441561. The reversal of 21344441413 is 31414444312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10424818404 + 10919623009 = 102102^2 + 104497^2 .

It is a cyclic number.

It is not a de Polignac number, because 21344441413 - 2⁵ = 21344441381 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 (21344741413) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 288456 + ... + 354817.

It is an arithmetic number, because the mean of its divisors is an integer number (5336279467).

Almost surely, 2^21344441413 is an apocalyptic number.

It is an amenable number.

21344441413 is a deficient number, since it is larger than the sum of its proper divisors (676455).

21344441413 is an equidigital number, since it uses as much as digits as its factorization.

21344441413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 676454.

The product of its digits is 18432, while the sum is 31.

Adding to 21344441413 its reverse (31414444312), we get a palindrome (52758885725).

The spelling of 21344441413 in words is "twenty-one billion, three hundred forty-four million, four hundred forty-one thousand, four hundred thirteen".