1215785056 has 24 divisors (see below), whose sum is σ = 2534376600. Its totient is φ = 572133888.

The previous prime is 1215785047. The next prime is 1215785069. The reversal of 1215785056 is 6505875121.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1116906 + ... + 1117993.

It is an arithmetic number, because the mean of its divisors is an integer number (105599025).

Almost surely, 2^1215785056 is an apocalyptic number.

1215785056 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1215785056 is an abundant number, since it is smaller than the sum of its proper divisors (1318591544).

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

1215785056 is a wasteful number, since it uses less digits than its factorization.

1215785056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2234926 (or 2234918 counting only the distinct ones).

The product of its (nonzero) digits is 84000, while the sum is 40.

The square root of 1215785056 is about 34868.1094411498. The cubic root of 1215785056 is about 1067.2977657693.

The spelling of 1215785056 in words is "one billion, two hundred fifteen million, seven hundred eighty-five thousand, fifty-six".