19891012 has 12 divisors (see below), whose sum is σ = 34856640. Its totient is φ = 9931976.

The previous prime is 19891007. The next prime is 19891019. The reversal of 19891012 is 21019891.

It is not an unprimeable number, because it can be changed into a prime (19891019) 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 3 ways as a sum of consecutive naturals, for example, 393 + ... + 6319.

It is an arithmetic number, because the mean of its divisors is an integer number (2904720).

Almost surely, 2^19891012 is an apocalyptic number.

It is an amenable number.

19891012 is a deficient number, since it is larger than the sum of its proper divisors (14965628).

19891012 is a wasteful number, since it uses less digits than its factorization.

19891012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6770 (or 6768 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 31.

The square root of 19891012 is about 4459.9340802303. The cubic root of 19891012 is about 270.9477983901.

The spelling of 19891012 in words is "nineteen million, eight hundred ninety-one thousand, twelve".