16689840 has 80 divisors (see below), whose sum is σ = 52148448. Its totient is φ = 4415488.

The previous prime is 16689839. The next prime is 16689851. The reversal of 16689840 is 4898661.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 16689792 and 16689801.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47104 + ... + 47456.

Almost surely, 2^16689840 is an apocalyptic number.

16689840 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 16689840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26074224).

16689840 is an abundant number, since it is smaller than the sum of its proper divisors (35458608).

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

16689840 is a wasteful number, since it uses less digits than its factorization.

16689840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 566 (or 560 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 42.

The square root of 16689840 is about 4085.3200609010. The cubic root of 16689840 is about 255.5548089315.

The spelling of 16689840 in words is "sixteen million, six hundred eighty-nine thousand, eight hundred forty".