19990660 has 48 divisors (see below), whose sum is σ = 45642240. Its totient is φ = 7326720.

The previous prime is 19990643. The next prime is 19990673. The reversal of 19990660 is 6609991.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10932 + ... + 12628.

It is an arithmetic number, because the mean of its divisors is an integer number (950880).

Almost surely, 2^19990660 is an apocalyptic number.

19990660 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 19990660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22821120).

19990660 is an abundant number, since it is smaller than the sum of its proper divisors (25651580).

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

19990660 is a wasteful number, since it uses less digits than its factorization.

19990660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1756 (or 1754 counting only the distinct ones).

The product of its (nonzero) digits is 26244, while the sum is 40.

The square root of 19990660 is about 4471.0915893102. The cubic root of 19990660 is about 271.3995006459.

The spelling of 19990660 in words is "nineteen million, nine hundred ninety thousand, six hundred sixty".