19869142 has 4 divisors (see below), whose sum is σ = 29803716. Its totient is φ = 9934570.

The previous prime is 19869131. The next prime is 19869167. The reversal of 19869142 is 24196891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24196891 = 2557 ⋅9463.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 19869095 and 19869104.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4967284 + ... + 4967287.

It is an arithmetic number, because the mean of its divisors is an integer number (7450929).

Almost surely, 2^19869142 is an apocalyptic number.

19869142 is a deficient number, since it is larger than the sum of its proper divisors (9934574).

19869142 is an equidigital number, since it uses as much as digits as its factorization.

19869142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9934573.

The product of its digits is 31104, while the sum is 40.

The square root of 19869142 is about 4457.4815759574. The cubic root of 19869142 is about 270.8484603674.

The spelling of 19869142 in words is "nineteen million, eight hundred sixty-nine thousand, one hundred forty-two".