19966680 has 96 divisors (see below), whose sum is σ = 66690000. Its totient is φ = 5177088.

The previous prime is 19966679. The next prime is 19966699. The reversal of 19966680 is 8666991.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12571 + ... + 14069.

Almost surely, 2^19966680 is an apocalyptic number.

19966680 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 19966680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33345000).

19966680 is an abundant number, since it is smaller than the sum of its proper divisors (46723320).

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

19966680 is a wasteful number, since it uses less digits than its factorization.

19966680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1553 (or 1546 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The square root of 19966680 is about 4468.4091128723. The cubic root of 19966680 is about 271.2909372123.

The spelling of 19966680 in words is "nineteen million, nine hundred sixty-six thousand, six hundred eighty".