13515231211 has 4 divisors (see below), whose sum is σ = 13646447152. Its totient is φ = 13384015272.

The previous prime is 13515231209. The next prime is 13515231269. The reversal of 13515231211 is 11213251531.

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 13515231211 - 2¹ = 13515231209 is a prime.

It is a super-2 number, since 2×13515231211² (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 (13515231011) 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, 65607816 + ... + 65608021.

It is an arithmetic number, because the mean of its divisors is an integer number (3411611788).

Almost surely, 2^13515231211 is an apocalyptic number.

13515231211 is a deficient number, since it is larger than the sum of its proper divisors (131215941).

13515231211 is a wasteful number, since it uses less digits than its factorization.

13515231211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131215940.

The product of its digits is 900, while the sum is 25.

Adding to 13515231211 its reverse (11213251531), we get a palindrome (24728482742).

The spelling of 13515231211 in words is "thirteen billion, five hundred fifteen million, two hundred thirty-one thousand, two hundred eleven".