21013115115 has 16 divisors (see below), whose sum is σ = 35598689568. Its totient is φ = 10547759616.

The previous prime is 21013115093. The next prime is 21013115119. The reversal of 21013115115 is 51151131012.

It is not a de Polignac number, because 21013115115 - 2¹⁰ = 21013114091 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21013115091 and 21013115100.

It is not an unprimeable number, because it can be changed into a prime (21013115119) 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 15 ways as a sum of consecutive naturals, for example, 41201932 + ... + 41202441.

It is an arithmetic number, because the mean of its divisors is an integer number (2224918098).

Almost surely, 2^21013115115 is an apocalyptic number.

21013115115 is a deficient number, since it is larger than the sum of its proper divisors (14585574453).

21013115115 is a wasteful number, since it uses less digits than its factorization.

21013115115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82404398.

The product of its (nonzero) digits is 150, while the sum is 21.

Adding to 21013115115 its reverse (51151131012), we get a palindrome (72164246127).

The spelling of 21013115115 in words is "twenty-one billion, thirteen million, one hundred fifteen thousand, one hundred fifteen".