16609687920 has 240 divisors, whose sum is σ = 63903290880. Its totient is φ = 3787347456.

The previous prime is 16609687907. The next prime is 16609687937. The reversal of 16609687920 is 2978690661.

16609687920 is a `hidden beast` number, since 1 + 6 + 609 + 6 + 8 + 7 + 9 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2208807 + ... + 2216313.

It is an arithmetic number, because the mean of its divisors is an integer number (266263712).

Almost surely, 2^16609687920 is an apocalyptic number.

16609687920 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 16609687920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31951645440).

16609687920 is an abundant number, since it is smaller than the sum of its proper divisors (47293602960).

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

16609687920 is a wasteful number, since it uses less digits than its factorization.

16609687920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7972 (or 7963 counting only the distinct ones).

The product of its (nonzero) digits is 1959552, while the sum is 54.

It can be divided in two parts, 166096 and 87920, that added together give a square (254016 = 504²).

The spelling of 16609687920 in words is "sixteen billion, six hundred nine million, six hundred eighty-seven thousand, nine hundred twenty".