19803945 has 16 divisors (see below), whose sum is σ = 36213120. Its totient is φ = 9053184.

The previous prime is 19803937. The next prime is 19803983. The reversal of 19803945 is 54930891.

It is not a de Polignac number, because 19803945 - 2³ = 19803937 is a prime.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 94200 + ... + 94409.

It is an arithmetic number, because the mean of its divisors is an integer number (2263320).

Almost surely, 2^19803945 is an apocalyptic number.

19803945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

19803945 is a deficient number, since it is larger than the sum of its proper divisors (16409175).

19803945 is a wasteful number, since it uses less digits than its factorization.

19803945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188624.

The product of its (nonzero) digits is 38880, while the sum is 39.

The square root of 19803945 is about 4450.1623565888. The cubic root of 19803945 is about 270.5518889846.

The spelling of 19803945 in words is "nineteen million, eight hundred three thousand, nine hundred forty-five".