1215881158 has 32 divisors (see below), whose sum is σ = 1943438112. Its totient is φ = 569721600.

The previous prime is 1215881141. The next prime is 1215881171. The reversal of 1215881158 is 8511885121.

It is a super-3 number, since 3×1215881158³ (a number of 28 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 1215881158.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 212260 + ... + 217912.

It is an arithmetic number, because the mean of its divisors is an integer number (60732441).

Almost surely, 2^1215881158 is an apocalyptic number.

1215881158 is a deficient number, since it is larger than the sum of its proper divisors (727556954).

1215881158 is a wasteful number, since it uses less digits than its factorization.

1215881158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5800.

The product of its digits is 25600, while the sum is 40.

The square root of 1215881158 is about 34869.4874926489. The cubic root of 1215881158 is about 1067.3258866247.

The spelling of 1215881158 in words is "one billion, two hundred fifteen million, eight hundred eighty-one thousand, one hundred fifty-eight".