19788345 has 24 divisors (see below), whose sum is σ = 34951176. Its totient is φ = 10353408.

The previous prime is 19788343. The next prime is 19788347. The reversal of 19788345 is 54388791.

It is an interprime number because it is at equal distance from previous prime (19788343) and next prime (19788347).

It can be written as a sum of positive squares in 4 ways, for example, as 9884736 + 9903609 = 3144^2 + 3147^2 .

It is not a de Polignac number, because 19788345 - 2¹ = 19788343 is a prime.

It is a Smith number, since the sum of its digits (45) 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 (45).

It is a self number, because there is not a number n which added to its sum of digits gives 19788345.

It is not an unprimeable number, because it can be changed into a prime (19788343) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1764 + ... + 6533.

It is an arithmetic number, because the mean of its divisors is an integer number (1456299).

Almost surely, 2^19788345 is an apocalyptic number.

19788345 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

19788345 is a deficient number, since it is larger than the sum of its proper divisors (15162831).

19788345 is a wasteful number, since it uses less digits than its factorization.

19788345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8361 (or 8358 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 19788345 is about 4448.4092662434. The cubic root of 19788345 is about 270.4808304459.

The spelling of 19788345 in words is "nineteen million, seven hundred eighty-eight thousand, three hundred forty-five".