19871842 has 8 divisors (see below), whose sum is σ = 29875500. Its totient is φ = 9913344.

The previous prime is 19871773. The next prime is 19871881. The reversal of 19871842 is 24817891.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 17564481 + 2307361 = 4191^2 + 1519^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 19871795 and 19871804.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10167 + ... + 11962.

Almost surely, 2^19871842 is an apocalyptic number.

19871842 is a deficient number, since it is larger than the sum of its proper divisors (10003658).

19871842 is a wasteful number, since it uses less digits than its factorization.

19871842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22580.

The product of its digits is 32256, while the sum is 40.

The square root of 19871842 is about 4457.7844272688. The cubic root of 19871842 is about 270.8607282637.

The spelling of 19871842 in words is "nineteen million, eight hundred seventy-one thousand, eight hundred forty-two".