19996091 has 4 divisors (see below), whose sum is σ = 20097792. Its totient is φ = 19894392.

The previous prime is 19996073. The next prime is 19996099. The reversal of 19996091 is 19069991.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19069991 = 31 ⋅615161.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19996091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19996099) 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, 50555 + ... + 50948.

It is an arithmetic number, because the mean of its divisors is an integer number (5024448).

Almost surely, 2^19996091 is an apocalyptic number.

19996091 is a deficient number, since it is larger than the sum of its proper divisors (101701).

19996091 is a wasteful number, since it uses less digits than its factorization.

19996091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101700.

The product of its (nonzero) digits is 39366, while the sum is 44.

The square root of 19996091 is about 4471.6988941564. The cubic root of 19996091 is about 271.4240760765.

The spelling of 19996091 in words is "nineteen million, nine hundred ninety-six thousand, ninety-one".