19782139 has 8 divisors (see below), whose sum is σ = 22230432. Its totient is φ = 17466240.

The previous prime is 19782127. The next prime is 19782143. The reversal of 19782139 is 93128791.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19782139 - 2⁷ = 19782011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19782109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32782 + ... + 33379.

It is an arithmetic number, because the mean of its divisors is an integer number (2778804).

Almost surely, 2^19782139 is an apocalyptic number.

19782139 is a deficient number, since it is larger than the sum of its proper divisors (2448293).

19782139 is a wasteful number, since it uses less digits than its factorization.

19782139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66197.

The product of its digits is 27216, while the sum is 40.

The square root of 19782139 is about 4447.7116588196. The cubic root of 19782139 is about 270.4525515180.

The spelling of 19782139 in words is "nineteen million, seven hundred eighty-two thousand, one hundred thirty-nine".