21101201212013 has 4 divisors (see below), whose sum is σ = 22724370536028. Its totient is φ = 19478031888000.

The previous prime is 21101201212009. The next prime is 21101201212019. The reversal of 21101201212013 is 31021210210112.

It is a happy number.

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 10290763558084 + 10810437653929 = 3207922^2 + 3287923^2 .

It is a cyclic number.

It is not a de Polignac number, because 21101201212013 - 2² = 21101201212009 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21101201211982 and 21101201212000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101201212019) 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, 811584661988 + ... + 811584662013.

It is an arithmetic number, because the mean of its divisors is an integer number (5681092634007).

Almost surely, 2^{21101201212013} is an apocalyptic number.

It is an amenable number.

21101201212013 is a deficient number, since it is larger than the sum of its proper divisors (1623169324015).

21101201212013 is a wasteful number, since it uses less digits than its factorization.

21101201212013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1623169324014.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 21101201212013 its reverse (31021210210112), we get a palindrome (52122411422125).

The spelling of 21101201212013 in words is "twenty-one trillion, one hundred one billion, two hundred one million, two hundred twelve thousand, thirteen".