1215321143 has 16 divisors (see below), whose sum is σ = 1300390560. Its totient is φ = 1131826176.

The previous prime is 1215321131. The next prime is 1215321161. The reversal of 1215321143 is 3411235121.

It is a cyclic number.

It is not a de Polignac number, because 1215321143 - 2²⁰ = 1214272567 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215321043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 754523 + ... + 756131.

It is an arithmetic number, because the mean of its divisors is an integer number (81274410).

Almost surely, 2^1215321143 is an apocalyptic number.

1215321143 is a deficient number, since it is larger than the sum of its proper divisors (85069417).

1215321143 is a wasteful number, since it uses less digits than its factorization.

1215321143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2066.

The product of its digits is 720, while the sum is 23.

The square root of 1215321143 is about 34861.4564096224. The cubic root of 1215321143 is about 1067.1619971710.

Adding to 1215321143 its reverse (3411235121), we get a palindrome (4626556264).

The spelling of 1215321143 in words is "one billion, two hundred fifteen million, three hundred twenty-one thousand, one hundred forty-three".