21011320013213 has 4 divisors (see below), whose sum is σ = 21207687490080. Its totient is φ = 20814952536348.

The previous prime is 21011320013183. The next prime is 21011320013221. The reversal of 21011320013213 is 31231002311012.

It is a happy number.

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 a de Polignac number, because none of the positive numbers 2^k-21011320013213 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 (21011320013813) 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, 98183738273 + ... + 98183738486.

It is an arithmetic number, because the mean of its divisors is an integer number (5301921872520).

Almost surely, 2^{21011320013213} is an apocalyptic number.

It is an amenable number.

21011320013213 is a deficient number, since it is larger than the sum of its proper divisors (196367476867).

21011320013213 is a wasteful number, since it uses less digits than its factorization.

21011320013213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196367476866.

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

Adding to 21011320013213 its reverse (31231002311012), we get a palindrome (52242322324225).

The spelling of 21011320013213 in words is "twenty-one trillion, eleven billion, three hundred twenty million, thirteen thousand, two hundred thirteen".