11971547172 has 192 divisors, whose sum is σ = 34037203200. Its totient is φ = 3616773120.

The previous prime is 11971547167. The next prime is 11971547183. The reversal of 11971547172 is 27174517911.

11971547172 is a `hidden beast` number, since 1 + 1 + 97 + 1 + 547 + 17 + 2 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 20965647 + ... + 20966217.

It is an arithmetic number, because the mean of its divisors is an integer number (177277100).

Almost surely, 2^11971547172 is an apocalyptic number.

11971547172 is a gapful number since it is divisible by the number (12) 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 11971547172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17018601600).

11971547172 is an abundant number, since it is smaller than the sum of its proper divisors (22065656028).

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

11971547172 is a wasteful number, since it uses less digits than its factorization.

11971547172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 843 (or 835 counting only the distinct ones).

The product of its digits is 123480, while the sum is 45.

The spelling of 11971547172 in words is "eleven billion, nine hundred seventy-one million, five hundred forty-seven thousand, one hundred seventy-two".