19242187 has 4 divisors (see below), whose sum is σ = 19380760. Its totient is φ = 19103616.

The previous prime is 19242173. The next prime is 19242203. The reversal of 19242187 is 78124291.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78124291 = 7 ⋅11160613.

It is a cyclic number.

It is not a de Polignac number, because 19242187 - 2⁷ = 19242059 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19242107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69078 + ... + 69355.

It is an arithmetic number, because the mean of its divisors is an integer number (4845190).

Almost surely, 2^19242187 is an apocalyptic number.

19242187 is a deficient number, since it is larger than the sum of its proper divisors (138573).

19242187 is a wasteful number, since it uses less digits than its factorization.

19242187 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138572.

The product of its digits is 8064, while the sum is 34.

The square root of 19242187 is about 4386.5917293498. The cubic root of 19242187 is about 267.9691571768.

The spelling of 19242187 in words is "nineteen million, two hundred forty-two thousand, one hundred eighty-seven".