16865437680 has 800 divisors, whose sum is σ = 74138004864. Its totient is φ = 3457769472.

The previous prime is 16865437679. The next prime is 16865437703. The reversal of 16865437680 is 8673456861.

16865437680 is a `hidden beast` number, since 16 + 8 + 6 + 543 + 7 + 6 + 80 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 21817774 + ... + 21818546.

Almost surely, 2^16865437680 is an apocalyptic number.

16865437680 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 16865437680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37069002432).

16865437680 is an abundant number, since it is smaller than the sum of its proper divisors (57272567184).

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

16865437680 is a wasteful number, since it uses less digits than its factorization.

16865437680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 855 (or 840 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 54.

The spelling of 16865437680 in words is "sixteen billion, eight hundred sixty-five million, four hundred thirty-seven thousand, six hundred eighty".