16661913408 has 448 divisors, whose sum is σ = 58560614400. Its totient is φ = 4546160640.

The previous prime is 16661913361. The next prime is 16661913421. The reversal of 16661913408 is 80431916661.

It is a tau number, because it is divible by the number of its divisors (448).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 26405253 + ... + 26405883.

Almost surely, 2^16661913408 is an apocalyptic number.

16661913408 is a gapful number since it is divisible by the number (18) 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 16661913408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29280307200).

16661913408 is an abundant number, since it is smaller than the sum of its proper divisors (41898700992).

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

16661913408 is a wasteful number, since it uses less digits than its factorization.

16661913408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 755 (or 739 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The spelling of 16661913408 in words is "sixteen billion, six hundred sixty-one million, nine hundred thirteen thousand, four hundred eight".