16945643520 has 648 divisors, whose sum is σ = 67352925276. Its totient is φ = 3925868544.

The previous prime is 16945643513. The next prime is 16945643527. The reversal of 16945643520 is 2534654961.

16945643520 is a `hidden beast` number, since 1 + 69 + 4 + 5 + 64 + 3 + 520 = 666.

It is an interprime number because it is at equal distance from previous prime (16945643513) and next prime (16945643527).

It can be written as a sum of positive squares in 6 ways, for example, as 3497066496 + 13448577024 = 59136^2 + 115968^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (16945643527) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 996802552 + ... + 996802568.

Almost surely, 2^16945643520 is an apocalyptic number.

16945643520 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 16945643520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33676462638).

16945643520 is an abundant number, since it is smaller than the sum of its proper divisors (50407281756).

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

16945643520 is an equidigital number, since it uses as much as digits as its factorization.

16945643520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88 (or 40 counting only the distinct ones).

The product of its (nonzero) digits is 777600, while the sum is 45.

The spelling of 16945643520 in words is "sixteen billion, nine hundred forty-five million, six hundred forty-three thousand, five hundred twenty".