11985651972 has 180 divisors, whose sum is σ = 37795443840. Its totient is φ = 3244015008.

The previous prime is 11985651971. The next prime is 11985652009. The reversal of 11985651972 is 27915658911.

It is a happy number.

11985651972 is a `hidden beast` number, since 1 + 1 + 9 + 8 + 56 + 519 + 72 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (11985651971) by changing a digit.

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 59 ways as a sum of consecutive naturals, for example, 811429 + ... + 826067.

It is an arithmetic number, because the mean of its divisors is an integer number (209974688).

Almost surely, 2^11985651972 is an apocalyptic number.

11985651972 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 11985651972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18897721920).

11985651972 is an abundant number, since it is smaller than the sum of its proper divisors (25809791868).

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

11985651972 is a wasteful number, since it uses less digits than its factorization.

11985651972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14700 (or 14670 counting only the distinct ones).

The product of its digits is 1360800, while the sum is 54.

The spelling of 11985651972 in words is "eleven billion, nine hundred eighty-five million, six hundred fifty-one thousand, nine hundred seventy-two".