11981039616 has 384 divisors, whose sum is σ = 43699219200. Its totient is φ = 3158507520.

The previous prime is 11981039593. The next prime is 11981039617. The reversal of 11981039616 is 61693018911.

11981039616 is a `hidden beast` number, since 1 + 19 + 8 + 10 + 3 + 9 + 616 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a super-2 number, since 2×11981039616² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (11981039617) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5030746 + ... + 5033126.

It is an arithmetic number, because the mean of its divisors is an integer number (113800050).

Almost surely, 2^11981039616 is an apocalyptic number.

11981039616 is a gapful number since it is divisible by the number (16) 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 11981039616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21849609600).

11981039616 is an abundant number, since it is smaller than the sum of its proper divisors (31718179584).

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

11981039616 is a wasteful number, since it uses less digits than its factorization.

11981039616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2432 (or 2406 counting only the distinct ones).

The product of its (nonzero) digits is 69984, while the sum is 45.

The spelling of 11981039616 in words is "eleven billion, nine hundred eighty-one million, thirty-nine thousand, six hundred sixteen".