11810989866 has 48 divisors (see below), whose sum is σ = 25611719616. Its totient is φ = 3629478528.

The previous prime is 11810989859. The next prime is 11810989901. The reversal of 11810989866 is 66898901811.

It is a super-2 number, since 2×11810989866² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 827446 + ... + 841598.

It is an arithmetic number, because the mean of its divisors is an integer number (533577492).

Almost surely, 2^11810989866 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11810989866, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12805859808).

11810989866 is an abundant number, since it is smaller than the sum of its proper divisors (13800729750).

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

11810989866 is a wasteful number, since it uses less digits than its factorization.

11810989866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15007 (or 14994 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 57.

The spelling of 11810989866 in words is "eleven billion, eight hundred ten million, nine hundred eighty-nine thousand, eight hundred sixty-six".