19870018 has 32 divisors (see below), whose sum is σ = 35354880. Its totient is φ = 8199360.

The previous prime is 19870013. The next prime is 19870021. The reversal of 19870018 is 81007891.

It is not an unprimeable number, because it can be changed into a prime (19870013) 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 15 ways as a sum of consecutive naturals, for example, 45043 + ... + 45481.

It is an arithmetic number, because the mean of its divisors is an integer number (1104840).

Almost surely, 2^19870018 is an apocalyptic number.

19870018 is a deficient number, since it is larger than the sum of its proper divisors (15484862).

19870018 is a wasteful number, since it uses less digits than its factorization.

19870018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562.

The product of its (nonzero) digits is 4032, while the sum is 34.

The square root of 19870018 is about 4457.5798366378. The cubic root of 19870018 is about 270.8524407400.

The spelling of 19870018 in words is "nineteen million, eight hundred seventy thousand, eighteen".