1215111713 has 4 divisors (see below), whose sum is σ = 1225865028. Its totient is φ = 1204358400.

The previous prime is 1215111707. The next prime is 1215111739. The reversal of 1215111713 is 3171115121.

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

It can be written as a sum of positive squares in 2 ways, for example, as 634687249 + 580424464 = 25193^2 + 24092^2 .

It is a cyclic number.

It is not a de Polignac number, because 1215111713 - 2²⁸ = 946676257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1215111913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5376488 + ... + 5376713.

It is an arithmetic number, because the mean of its divisors is an integer number (306466257).

Almost surely, 2^1215111713 is an apocalyptic number.

It is an amenable number.

1215111713 is a deficient number, since it is larger than the sum of its proper divisors (10753315).

1215111713 is a wasteful number, since it uses less digits than its factorization.

1215111713 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10753314.

The product of its digits is 210, while the sum is 23.

The square root of 1215111713 is about 34858.4525330658. The cubic root of 1215111713 is about 1067.1006941490.

Adding to 1215111713 its reverse (3171115121), we get a palindrome (4386226834).

The spelling of 1215111713 in words is "one billion, two hundred fifteen million, one hundred eleven thousand, seven hundred thirteen".