19913906 has 16 divisors (see below), whose sum is σ = 31497984. Its totient is φ = 9423744.

The previous prime is 19913899. The next prime is 19913911. The reversal of 19913906 is 60931991.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 19913906.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2231 + ... + 6693.

It is an arithmetic number, because the mean of its divisors is an integer number (1968624).

Almost surely, 2^19913906 is an apocalyptic number.

It is a pronic number, being equal to 4462×4463.

19913906 is a deficient number, since it is larger than the sum of its proper divisors (11584078).

19913906 is a wasteful number, since it uses less digits than its factorization.

19913906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4585.

The product of its (nonzero) digits is 13122, while the sum is 38.

The square root of 19913906 is about 4462.4999719888. The cubic root of 19913906 is about 271.0517096535.

The spelling of 19913906 in words is "nineteen million, nine hundred thirteen thousand, nine hundred six".