11811172880 has 80 divisors (see below), whose sum is σ = 29600490864. Its totient is φ = 4357048320.

The previous prime is 11811172873. The next prime is 11811172903. The reversal of 11811172880 is 8827111811.

It can be written as a sum of positive squares in 8 ways, for example, as 39790864 + 11771382016 = 6308^2 + 108496^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1281890 + ... + 1291070.

Almost surely, 2^11811172880 is an apocalyptic number.

11811172880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11811172880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14800245432).

11811172880 is an abundant number, since it is smaller than the sum of its proper divisors (17789317984).

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

11811172880 is a wasteful number, since it uses less digits than its factorization.

11811172880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10444 (or 10438 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 38.

The spelling of 11811172880 in words is "eleven billion, eight hundred eleven million, one hundred seventy-two thousand, eight hundred eighty".