1215212361 has 16 divisors (see below), whose sum is σ = 1768815360. Its totient is φ = 735978320.

The previous prime is 1215212351. The next prime is 1215212363. The reversal of 1215212361 is 1632125121.

It is a happy number.

It is not a de Polignac number, because 1215212361 - 2⁵ = 1215212329 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1215212363) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38170 + ... + 62348.

It is an arithmetic number, because the mean of its divisors is an integer number (110550960).

Almost surely, 2^1215212361 is an apocalyptic number.

1215212361 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1215212361 is a deficient number, since it is larger than the sum of its proper divisors (553602999).

1215212361 is a wasteful number, since it uses less digits than its factorization.

1215212361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25716.

The product of its digits is 720, while the sum is 24.

The square root of 1215212361 is about 34859.8961702412. The cubic root of 1215212361 is about 1067.1301560726.

Adding to 1215212361 its reverse (1632125121), we get a palindrome (2847337482).

The spelling of 1215212361 in words is "one billion, two hundred fifteen million, two hundred twelve thousand, three hundred sixty-one".