19401689 has 4 divisors (see below), whose sum is σ = 19647360. Its totient is φ = 19156020.

The previous prime is 19401617. The next prime is 19401713. The reversal of 19401689 is 98610491.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 19401689 - 2⁸ = 19401433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19401289) 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 3 ways as a sum of consecutive naturals, for example, 122717 + ... + 122874.

It is an arithmetic number, because the mean of its divisors is an integer number (4911840).

Almost surely, 2^19401689 is an apocalyptic number.

It is an amenable number.

19401689 is a deficient number, since it is larger than the sum of its proper divisors (245671).

19401689 is an equidigital number, since it uses as much as digits as its factorization.

19401689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245670.

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 19401689 is about 4404.7348387843. The cubic root of 19401689 is about 268.7075358182.

The spelling of 19401689 in words is "nineteen million, four hundred one thousand, six hundred eighty-nine".