19880191 has 8 divisors (see below), whose sum is σ = 21119184. Its totient is φ = 18648960.

The previous prime is 19880149. The next prime is 19880221. The reversal of 19880191 is 19108891.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19880191 - 2⁹ = 19879679 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 19880191.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19880101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3861 + ... + 7393.

It is an arithmetic number, because the mean of its divisors is an integer number (2639898).

Almost surely, 2^19880191 is an apocalyptic number.

19880191 is a deficient number, since it is larger than the sum of its proper divisors (1238993).

19880191 is a wasteful number, since it uses less digits than its factorization.

19880191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3881.

The product of its (nonzero) digits is 5184, while the sum is 37.

The square root of 19880191 is about 4458.7207806724. The cubic root of 19880191 is about 270.8986562959.

The spelling of 19880191 in words is "nineteen million, eight hundred eighty thousand, one hundred ninety-one".