19994478 has 16 divisors (see below), whose sum is σ = 45701760. Its totient is φ = 5712696.

The previous prime is 19994477. The next prime is 19994489. The reversal of 19994478 is 87449991.

It is a self number, because there is not a number n which added to its sum of digits gives 19994478.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19994477) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 237988 + ... + 238071.

It is an arithmetic number, because the mean of its divisors is an integer number (2856360).

Almost surely, 2^19994478 is an apocalyptic number.

19994478 is an abundant number, since it is smaller than the sum of its proper divisors (25707282).

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

19994478 is a wasteful number, since it uses less digits than its factorization.

19994478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476071.

The product of its digits is 653184, while the sum is 51.

The square root of 19994478 is about 4471.5185340106. The cubic root of 19994478 is about 271.4167776699.

The spelling of 19994478 in words is "nineteen million, nine hundred ninety-four thousand, four hundred seventy-eight".