21221311313 has 8 divisors (see below), whose sum is σ = 21380948736. Its totient is φ = 21062250000.

The previous prime is 21221311303. The next prime is 21221311357. The reversal of 21221311313 is 31311312212.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21221311313 - 2⁶ = 21221311249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21221311303) 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, 69938 + ... + 217563.

It is an arithmetic number, because the mean of its divisors is an integer number (2672618592).

Almost surely, 2^21221311313 is an apocalyptic number.

It is an amenable number.

21221311313 is a deficient number, since it is larger than the sum of its proper divisors (159637423).

21221311313 is a wasteful number, since it uses less digits than its factorization.

21221311313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288055.

The product of its digits is 216, while the sum is 20.

Adding to 21221311313 its reverse (31311312212), we get a palindrome (52532623525).

The spelling of 21221311313 in words is "twenty-one billion, two hundred twenty-one million, three hundred eleven thousand, three hundred thirteen".