21220013213 has 16 divisors (see below), whose sum is σ = 24381350016. Its totient is φ = 18091261440.

The previous prime is 21220013203. The next prime is 21220013251. The reversal of 21220013213 is 31231002212.

It is not a de Polignac number, because 21220013213 - 2³⁴ = 4040144029 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21220013191 and 21220013200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220013203) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3176645 + ... + 3183317.

It is an arithmetic number, because the mean of its divisors is an integer number (1523834376).

Almost surely, 2^21220013213 is an apocalyptic number.

It is an amenable number.

21220013213 is a deficient number, since it is larger than the sum of its proper divisors (3161336803).

21220013213 is a wasteful number, since it uses less digits than its factorization.

21220013213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9044.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21220013213 its reverse (31231002212), we get a palindrome (52451015425).

The spelling of 21220013213 in words is "twenty-one billion, two hundred twenty million, thirteen thousand, two hundred thirteen".