16991795969280 has 720 divisors, whose sum is σ = 66361643276544. Its totient is φ = 4117072527360.

The previous prime is 16991795969273. The next prime is 16991795969311. The reversal of 16991795969280 is 8296959719961.

16991795969280 is a `hidden beast` number, since 1 + 6 + 9 + 9 + 17 + 9 + 596 + 9 + 2 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

It is a super-2 number, since 2×16991795969280² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is a self number, because there is not a number n which added to its sum of digits gives 16991795969280.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3885613174 + ... + 3885617546.

Almost surely, 2^{16991795969280} is an apocalyptic number.

16991795969280 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 16991795969280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33180821638272).

16991795969280 is an abundant number, since it is smaller than the sum of its proper divisors (49369847307264).

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

16991795969280 is a wasteful number, since it uses less digits than its factorization.

16991795969280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7824 (or 7801 counting only the distinct ones).

The product of its (nonzero) digits is 1190427840, while the sum is 81.

The spelling of 16991795969280 in words is "sixteen trillion, nine hundred ninety-one billion, seven hundred ninety-five million, nine hundred sixty-nine thousand, two hundred eighty".