21013100131 has 4 divisors (see below), whose sum is σ = 21022972200. Its totient is φ = 21003228064.

The previous prime is 21013100093. The next prime is 21013100201. The reversal of 21013100131 is 13100131012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21013100131 - 2⁹ = 21013099619 is a prime.

It is a super-2 number, since 2×21013100131² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21013100831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4932841 + ... + 4937098.

It is an arithmetic number, because the mean of its divisors is an integer number (5255743050).

Almost surely, 2^21013100131 is an apocalyptic number.

21013100131 is a deficient number, since it is larger than the sum of its proper divisors (9872069).

21013100131 is an equidigital number, since it uses as much as digits as its factorization.

21013100131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9872068.

The product of its (nonzero) digits is 18, while the sum is 13.

Adding to 21013100131 its reverse (13100131012), we get a palindrome (34113231143).

The spelling of 21013100131 in words is "twenty-one billion, thirteen million, one hundred thousand, one hundred thirty-one".