19905966 has 32 divisors (see below), whose sum is σ = 44388000. Its totient is φ = 6612480.

The previous prime is 19905961. The next prime is 19905979. The reversal of 19905966 is 66950991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19905961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23836 + ... + 24656.

It is an arithmetic number, because the mean of its divisors is an integer number (1387125).

Almost surely, 2^19905966 is an apocalyptic number.

19905966 is an abundant number, since it is smaller than the sum of its proper divisors (24482034).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19905966 is a wasteful number, since it uses less digits than its factorization.

19905966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1281 (or 1275 counting only the distinct ones).

The product of its (nonzero) digits is 131220, while the sum is 45.

The square root of 19905966 is about 4461.6102474331. The cubic root of 19905966 is about 271.0156806148.

The spelling of 19905966 in words is "nineteen million, nine hundred five thousand, nine hundred sixty-six".