16684658640 has 800 divisors, whose sum is σ = 65948341536. Its totient is φ = 3881779200.

The previous prime is 16684658629. The next prime is 16684658671. The reversal of 16684658640 is 4685648661.

16684658640 is a `hidden beast` number, since 1 + 6 + 68 + 465 + 86 + 40 = 666.

It can be written as a sum of positive squares in 16 ways, for example, as 9585216 + 16675073424 = 3096^2 + 129132^2 .

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, 165194590 + ... + 165194690.

Almost surely, 2^16684658640 is an apocalyptic number.

16684658640 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 16684658640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32974170768).

16684658640 is an abundant number, since it is smaller than the sum of its proper divisors (49263682896).

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

16684658640 is a wasteful number, since it uses less digits than its factorization.

16684658640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229 (or 214 counting only the distinct ones).

The product of its (nonzero) digits is 6635520, while the sum is 54.

The spelling of 16684658640 in words is "sixteen billion, six hundred eighty-four million, six hundred fifty-eight thousand, six hundred forty".