21100131011 has 4 divisors (see below), whose sum is σ = 21124752792. Its totient is φ = 21075509232.

The previous prime is 21100130983. The next prime is 21100131029. The reversal of 21100131011 is 11013100112.

It is a happy number.

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 21100131011 - 2¹⁴ = 21100114627 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21100130983 and 21100131001.

It is not an unprimeable number, because it can be changed into a prime (21100131911) 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, 12309605 + ... + 12311318.

It is an arithmetic number, because the mean of its divisors is an integer number (5281188198).

Almost surely, 2^21100131011 is an apocalyptic number.

21100131011 is a deficient number, since it is larger than the sum of its proper divisors (24621781).

21100131011 is an equidigital number, since it uses as much as digits as its factorization.

21100131011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24621780.

The product of its (nonzero) digits is 6, while the sum is 11.

Adding to 21100131011 its reverse (11013100112), we get a palindrome (32113231123).

The spelling of 21100131011 in words is "twenty-one billion, one hundred million, one hundred thirty-one thousand, eleven".