19662139 has 4 divisors (see below), whose sum is σ = 22471024. Its totient is φ = 16853256.

The previous prime is 19662127. The next prime is 19662157. The reversal of 19662139 is 93126691.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 19662139 - 2⁵ = 19662107 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19662098 and 19662107.

It is not an unprimeable number, because it can be changed into a prime (19662179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1404432 + ... + 1404445.

It is an arithmetic number, because the mean of its divisors is an integer number (5617756).

Almost surely, 2^19662139 is an apocalyptic number.

19662139 is a deficient number, since it is larger than the sum of its proper divisors (2808885).

19662139 is an equidigital number, since it uses as much as digits as its factorization.

19662139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2808884.

The product of its digits is 17496, while the sum is 37.

The square root of 19662139 is about 4434.2010554326. The cubic root of 19662139 is about 269.9045799077.

The spelling of 19662139 in words is "nineteen million, six hundred sixty-two thousand, one hundred thirty-nine".