19872542 has 4 divisors (see below), whose sum is σ = 29808816. Its totient is φ = 9936270.

The previous prime is 19872497. The next prime is 19872551. The reversal of 19872542 is 24527891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24527891 = 127 ⋅193133.

It is a junction number, because it is equal to n+sod(n) for n = 19872496 and 19872505.

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, 4968134 + ... + 4968137.

It is an arithmetic number, because the mean of its divisors is an integer number (7452204).

Almost surely, 2^19872542 is an apocalyptic number.

19872542 is a deficient number, since it is larger than the sum of its proper divisors (9936274).

19872542 is an equidigital number, since it uses as much as digits as its factorization.

19872542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9936273.

The product of its digits is 40320, while the sum is 38.

The square root of 19872542 is about 4457.8629409169. The cubic root of 19872542 is about 270.8639086481.

The spelling of 19872542 in words is "nineteen million, eight hundred seventy-two thousand, five hundred forty-two".