21211313441 has 4 divisors (see below), whose sum is σ = 21212394372. Its totient is φ = 21210232512.

The previous prime is 21211313377. The next prime is 21211313477. The reversal of 21211313441 is 14431311212.

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 16709440225 + 4501873216 = 129265^2 + 67096^2 .

It is a cyclic number.

It is not a de Polignac number, because 21211313441 - 2⁶ = 21211313377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21211313041) 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, 510476 + ... + 550461.

It is an arithmetic number, because the mean of its divisors is an integer number (5303098593).

Almost surely, 2^21211313441 is an apocalyptic number.

It is an amenable number.

21211313441 is a deficient number, since it is larger than the sum of its proper divisors (1080931).

21211313441 is a wasteful number, since it uses less digits than its factorization.

21211313441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1080930.

The product of its digits is 576, while the sum is 23.

Adding to 21211313441 its reverse (14431311212), we get a palindrome (35642624653).

The spelling of 21211313441 in words is "twenty-one billion, two hundred eleven million, three hundred thirteen thousand, four hundred forty-one".