11997011520 has 896 divisors, whose sum is σ = 49526830080. Its totient is φ = 2707292160.

The previous prime is 11997011519. The next prime is 11997011557. The reversal of 11997011520 is 2511079911.

11997011520 is a `hidden beast` number, since 119 + 9 + 7 + 0 + 11 + 520 = 666.

It is a super-2 number, since 2×11997011520² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 116475789 + ... + 116475891.

It is an arithmetic number, because the mean of its divisors is an integer number (55275480).

Almost surely, 2^11997011520 is an apocalyptic number.

11997011520 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 11997011520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24763415040).

11997011520 is an abundant number, since it is smaller than the sum of its proper divisors (37529818560).

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

11997011520 is a wasteful number, since it uses less digits than its factorization.

11997011520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220 (or 204 counting only the distinct ones).

The product of its (nonzero) digits is 5670, while the sum is 36.

The spelling of 11997011520 in words is "eleven billion, nine hundred ninety-seven million, eleven thousand, five hundred twenty".