19666368 has 112 divisors (see below), whose sum is σ = 60960000. Its totient is φ = 6200064.

The previous prime is 19666337. The next prime is 19666373. The reversal of 19666368 is 86366691.

It is a super-2 number, since 2×19666368² = 773532060622848, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

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, 32533 + ... + 33131.

Almost surely, 2^19666368 is an apocalyptic number.

19666368 is a gapful number since it is divisible by the number (18) 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 19666368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30480000).

19666368 is an abundant number, since it is smaller than the sum of its proper divisors (41293632).

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

19666368 is a wasteful number, since it uses less digits than its factorization.

19666368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 639 (or 623 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The square root of 19666368 is about 4434.6778913468. The cubic root of 19666368 is about 269.9239291868.

It can be divided in two parts, 196 and 66368, that added together give a square (66564 = 258²).

The spelling of 19666368 in words is "nineteen million, six hundred sixty-six thousand, three hundred sixty-eight".