1982009191 has 4 divisors (see below), whose sum is σ = 2028102472. Its totient is φ = 1935915912.

The previous prime is 1982009179. The next prime is 1982009231. The reversal of 1982009191 is 1919002891.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1982009191 - 2²⁵ = 1948454759 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 (1982009891) 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 3 ways as a sum of consecutive naturals, for example, 23046576 + ... + 23046661.

It is an arithmetic number, because the mean of its divisors is an integer number (507025618).

Almost surely, 2^1982009191 is an apocalyptic number.

1982009191 is a deficient number, since it is larger than the sum of its proper divisors (46093281).

1982009191 is an equidigital number, since it uses as much as digits as its factorization.

1982009191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46093280.

The product of its (nonzero) digits is 11664, while the sum is 40.

The square root of 1982009191 is about 44519.7618030465. The cubic root of 1982009191 is about 1256.1318320704.

The spelling of 1982009191 in words is "one billion, nine hundred eighty-two million, nine thousand, one hundred ninety-one".