1215640116 has 24 divisors (see below), whose sum is σ = 3151659840. Its totient is φ = 405213336.

The previous prime is 1215640109. The next prime is 1215640117. The reversal of 1215640116 is 6110465121.

1215640116 is a `hidden beast` number, since 1 + 2 + 1 + 5 + 640 + 1 + 16 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 1215640116.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215640117) 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, 5627856 + ... + 5628071.

It is an arithmetic number, because the mean of its divisors is an integer number (131319160).

Almost surely, 2^1215640116 is an apocalyptic number.

It is an amenable number.

1215640116 is an abundant number, since it is smaller than the sum of its proper divisors (1936019724).

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

1215640116 is a wasteful number, since it uses less digits than its factorization.

1215640116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11255940 (or 11255932 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 1215640116 is about 34866.0309757219. The cubic root of 1215640116 is about 1067.2553513954.

The spelling of 1215640116 in words is "one billion, two hundred fifteen million, six hundred forty thousand, one hundred sixteen".