19806404 has 24 divisors (see below), whose sum is σ = 36324288. Its totient is φ = 9431840.

The previous prime is 19806401. The next prime is 19806419. The reversal of 19806404 is 40460891.

It is a super-2 number, since 2×19806404² = 784587278822432, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19806401) 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 7 ways as a sum of consecutive naturals, for example, 42179 + ... + 42645.

It is an arithmetic number, because the mean of its divisors is an integer number (1513512).

Almost surely, 2^19806404 is an apocalyptic number.

It is an amenable number.

19806404 is a deficient number, since it is larger than the sum of its proper divisors (16517884).

19806404 is a wasteful number, since it uses less digits than its factorization.

19806404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 955 (or 953 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 19806404 is about 4450.4386300678. The cubic root of 19806404 is about 270.5630864095.

The spelling of 19806404 in words is "nineteen million, eight hundred six thousand, four hundred four".