16540991812800 has 4032 divisors, whose sum is σ = 80342314905600. Its totient is φ = 3229640294400.

The previous prime is 16540991812769. The next prime is 16540991812931. The reversal of 16540991812800 is 821819904561.

16540991812800 is a `hidden beast` number, since 1 + 6 + 540 + 9 + 9 + 1 + 8 + 12 + 80 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (4032).

It is a super-2 number, since 2×16540991812800² (a number of 27 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 575 ways as a sum of consecutive naturals, for example, 68634820680 + ... + 68634820920.

Almost surely, 2^{16540991812800} is an apocalyptic number.

16540991812800 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 16540991812800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40171157452800).

16540991812800 is an abundant number, since it is smaller than the sum of its proper divisors (63801323092800).

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

16540991812800 is a wasteful number, since it uses less digits than its factorization.

16540991812800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401 (or 367 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 54.

The spelling of 16540991812800 in words is "sixteen trillion, five hundred forty billion, nine hundred ninety-one million, eight hundred twelve thousand, eight hundred".