19966340 has 24 divisors (see below), whose sum is σ = 44136960. Its totient is φ = 7566048.

The previous prime is 19966339. The next prime is 19966343. The reversal of 19966340 is 4366991.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a junction number, because it is equal to n+sod(n) for n = 19966294 and 19966303.

It is not an unprimeable number, because it can be changed into a prime (19966343) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25892 + ... + 26651.

It is an arithmetic number, because the mean of its divisors is an integer number (1839040).

Almost surely, 2^19966340 is an apocalyptic number.

19966340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19966340 is an abundant number, since it is smaller than the sum of its proper divisors (24170620).

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

19966340 is a wasteful number, since it uses less digits than its factorization.

19966340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52571 (or 52569 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 38.

The square root of 19966340 is about 4468.3710678501. The cubic root of 19966340 is about 271.2893973228.

The spelling of 19966340 in words is "nineteen million, nine hundred sixty-six thousand, three hundred forty".