11556156820 has 48 divisors (see below), whose sum is σ = 27510215040. Its totient is φ = 4042313856.

The previous prime is 11556156811. The next prime is 11556156917. The reversal of 11556156820 is 2865165511.

11556156820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 1164712 + ... + 1174591.

It is an arithmetic number, because the mean of its divisors is an integer number (573129480).

Almost surely, 2^11556156820 is an apocalyptic number.

11556156820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11556156820 is an abundant number, since it is smaller than the sum of its proper divisors (15954058220).

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

11556156820 is a wasteful number, since it uses less digits than its factorization.

11556156820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2339344 (or 2339342 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 40.

The spelling of 11556156820 in words is "eleven billion, five hundred fifty-six million, one hundred fifty-six thousand, eight hundred twenty".