1216131136 has 56 divisors (see below), whose sum is σ = 2675900160. Its totient is φ = 543705600.

The previous prime is 1216131083. The next prime is 1216131143. The reversal of 1216131136 is 6311316121.

It is a self number, because there is not a number n which added to its sum of digits gives 1216131136.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 28785 + ... + 57103.

Almost surely, 2^1216131136 is an apocalyptic number.

1216131136 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1216131136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1337950080).

1216131136 is an abundant number, since it is smaller than the sum of its proper divisors (1459769024).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1216131136 is a wasteful number, since it uses less digits than its factorization.

1216131136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28403 (or 28393 counting only the distinct ones).

The product of its digits is 648, while the sum is 25.

The square root of 1216131136 is about 34873.0717889893. The cubic root of 1216131136 is about 1067.3990269165.

Adding to 1216131136 its reverse (6311316121), we get a palindrome (7527447257).

The spelling of 1216131136 in words is "one billion, two hundred sixteen million, one hundred thirty-one thousand, one hundred thirty-six".