19668616 has 16 divisors (see below), whose sum is σ = 40231440. Its totient is φ = 8940240.

The previous prime is 19668613. The next prime is 19668647. The reversal of 19668616 is 61686691.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (19668613) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111666 + ... + 111841.

It is an arithmetic number, because the mean of its divisors is an integer number (2514465).

Almost surely, 2^19668616 is an apocalyptic number.

It is an amenable number.

19668616 is an abundant number, since it is smaller than the sum of its proper divisors (20562824).

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

19668616 is a wasteful number, since it uses less digits than its factorization.

19668616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223524 (or 223520 counting only the distinct ones).

The product of its digits is 93312, while the sum is 43.

The square root of 19668616 is about 4434.9313410694. The cubic root of 19668616 is about 269.9342135104.

The spelling of 19668616 in words is "nineteen million, six hundred sixty-eight thousand, six hundred sixteen".