21131004113 has 4 divisors (see below), whose sum is σ = 21385594608. Its totient is φ = 20876413620.

The previous prime is 21131004101. The next prime is 21131004119. The reversal of 21131004113 is 31140013112.

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 not a de Polignac number, because 21131004113 - 2⁸ = 21131003857 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21131004091 and 21131004100.

It is not an unprimeable number, because it can be changed into a prime (21131004119) 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, 127295123 + ... + 127295288.

It is an arithmetic number, because the mean of its divisors is an integer number (5346398652).

Almost surely, 2^21131004113 is an apocalyptic number.

It is an amenable number.

21131004113 is a deficient number, since it is larger than the sum of its proper divisors (254590495).

21131004113 is an equidigital number, since it uses as much as digits as its factorization.

21131004113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254590494.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21131004113 its reverse (31140013112), we get a palindrome (52271017225).

The spelling of 21131004113 in words is "twenty-one billion, one hundred thirty-one million, four thousand, one hundred thirteen".