19794813 has 4 divisors (see below), whose sum is σ = 26393088. Its totient is φ = 13196540.

The previous prime is 19794809. The next prime is 19794821. The reversal of 19794813 is 31849791.

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, and also an emirpimes, since its reverse is a distinct semiprime: 31849791 = 3 ⋅10616597.

It is a cyclic number.

It is not a de Polignac number, because 19794813 - 2² = 19794809 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19794823) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3299133 + ... + 3299138.

It is an arithmetic number, because the mean of its divisors is an integer number (6598272).

Almost surely, 2^19794813 is an apocalyptic number.

It is an amenable number.

19794813 is a deficient number, since it is larger than the sum of its proper divisors (6598275).

19794813 is an equidigital number, since it uses as much as digits as its factorization.

19794813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6598274.

The product of its digits is 54432, while the sum is 42.

The square root of 19794813 is about 4449.1362082993. The cubic root of 19794813 is about 270.5102969397.

The spelling of 19794813 in words is "nineteen million, seven hundred ninety-four thousand, eight hundred thirteen".