19478902 has 4 divisors (see below), whose sum is σ = 29218356. Its totient is φ = 9739450.

The previous prime is 19478897. The next prime is 19478903. The reversal of 19478902 is 20987491.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 20987491 = 7 ⋅2998213.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a plaindrome in base 8.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19478903) 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 as a sum of consecutive naturals, namely, 4869724 + ... + 4869727.

It is an arithmetic number, because the mean of its divisors is an integer number (7304589).

Almost surely, 2^19478902 is an apocalyptic number.

19478902 is a deficient number, since it is larger than the sum of its proper divisors (9739454).

19478902 is an equidigital number, since it uses as much as digits as its factorization.

19478902 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9739453.

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 19478902 is about 4413.4909085666. The cubic root of 19478902 is about 269.0635229077.

The spelling of 19478902 in words is "nineteen million, four hundred seventy-eight thousand, nine hundred two".