19130021 has 4 divisors (see below), whose sum is σ = 19156512. Its totient is φ = 19103532.

The previous prime is 19130011. The next prime is 19130029. The reversal of 19130021 is 12003191.

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 19130021 - 2¹⁰ = 19128997 is a prime.

It is a super-5 number, since 5×19130021⁵ (a number of 38 digits) contains 55555 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19130029) 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 3 ways as a sum of consecutive naturals, for example, 12131 + ... + 13616.

It is an arithmetic number, because the mean of its divisors is an integer number (4789128).

Almost surely, 2^19130021 is an apocalyptic number.

It is an amenable number.

19130021 is a deficient number, since it is larger than the sum of its proper divisors (26491).

19130021 is an equidigital number, since it uses as much as digits as its factorization.

19130021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26490.

The product of its (nonzero) digits is 54, while the sum is 17.

The square root of 19130021 is about 4373.7879463915. The cubic root of 19130021 is about 267.4474628241.

The spelling of 19130021 in words is "nineteen million, one hundred thirty thousand, twenty-one".