11991020712 has 64 divisors (see below), whose sum is σ = 32713804800. Its totient is φ = 3632418240.

The previous prime is 11991020687. The next prime is 11991020719. The reversal of 11991020712 is 21702019911.

It is a super-2 number, since 2×11991020712² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (11991020719) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1057489 + ... + 1068767.

It is an arithmetic number, because the mean of its divisors is an integer number (511153200).

Almost surely, 2^11991020712 is an apocalyptic number.

11991020712 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

11991020712 is an abundant number, since it is smaller than the sum of its proper divisors (20722784088).

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

11991020712 is a wasteful number, since it uses less digits than its factorization.

11991020712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15326 (or 15322 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 33.

The spelling of 11991020712 in words is "eleven billion, nine hundred ninety-one million, twenty thousand, seven hundred twelve".