1217731312 has 40 divisors (see below), whose sum is σ = 2699827200. Its totient is φ = 521222592.

The previous prime is 1217731289. The next prime is 1217731313. The reversal of 1217731312 is 2131377121.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1217731313) 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 7 ways as a sum of consecutive naturals, for example, 87489 + ... + 100447.

It is an arithmetic number, because the mean of its divisors is an integer number (67495680).

Almost surely, 2^1217731312 is an apocalyptic number.

It is an amenable number.

1217731312 is an abundant number, since it is smaller than the sum of its proper divisors (1482095888).

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

1217731312 is a wasteful number, since it uses less digits than its factorization.

1217731312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13813 (or 13807 counting only the distinct ones).

The product of its digits is 1764, while the sum is 28.

The square root of 1217731312 is about 34896.0071068310. The cubic root of 1217731312 is about 1067.8669802114.

The spelling of 1217731312 in words is "one billion, two hundred seventeen million, seven hundred thirty-one thousand, three hundred twelve".