19368021 has 4 divisors (see below), whose sum is σ = 25824032. Its totient is φ = 12912012.

The previous prime is 19367977. The next prime is 19368023. The reversal of 19368021 is 12086391.

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 not a de Polignac number, because 19368021 - 2¹³ = 19359829 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19368021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19368023) 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, 3228001 + ... + 3228006.

It is an arithmetic number, because the mean of its divisors is an integer number (6456008).

Almost surely, 2^19368021 is an apocalyptic number.

It is an amenable number.

19368021 is a deficient number, since it is larger than the sum of its proper divisors (6456011).

19368021 is an equidigital number, since it uses as much as digits as its factorization.

19368021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6456010.

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 19368021 is about 4400.9113828842. The cubic root of 19368021 is about 268.5520152791.

The spelling of 19368021 in words is "nineteen million, three hundred sixty-eight thousand, twenty-one".