19959013 has 4 divisors (see below), whose sum is σ = 20044908. Its totient is φ = 19873120.

The previous prime is 19959001. The next prime is 19959019. The reversal of 19959013 is 31095991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31095991 = 1031 ⋅30161.

It can be written as a sum of positive squares in 2 ways, for example, as 2377764 + 17581249 = 1542^2 + 4193^2 .

It is a cyclic number.

It is not a de Polignac number, because 19959013 - 2⁹ = 19958501 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19959019) 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, 42598 + ... + 43063.

It is an arithmetic number, because the mean of its divisors is an integer number (5011227).

Almost surely, 2^19959013 is an apocalyptic number.

It is an amenable number.

19959013 is a deficient number, since it is larger than the sum of its proper divisors (85895).

19959013 is an equidigital number, since it uses as much as digits as its factorization.

19959013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85894.

The product of its (nonzero) digits is 10935, while the sum is 37.

The square root of 19959013 is about 4467.5511189017. The cubic root of 19959013 is about 271.2562084558.

The spelling of 19959013 in words is "nineteen million, nine hundred fifty-nine thousand, thirteen".