1216838140 has 48 divisors (see below), whose sum is σ = 2922393600. Its totient is φ = 416918592.

The previous prime is 1216838113. The next prime is 1216838191. The reversal of 1216838140 is 418386121.

It is a junction number, because it is equal to n+sod(n) for n = 1216838096 and 1216838105.

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, 401551 + ... + 404569.

It is an arithmetic number, because the mean of its divisors is an integer number (60883200).

Almost surely, 2^1216838140 is an apocalyptic number.

1216838140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1216838140 is an abundant number, since it is smaller than the sum of its proper divisors (1705555460).

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

1216838140 is a wasteful number, since it uses less digits than its factorization.

1216838140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5914 (or 5912 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 1216838140 is about 34883.2071346658. The cubic root of 1216838140 is about 1067.6058327906.

The spelling of 1216838140 in words is "one billion, two hundred sixteen million, eight hundred thirty-eight thousand, one hundred forty".