1982169121 has 4 divisors (see below), whose sum is σ = 1982484244. Its totient is φ = 1981854000.

The previous prime is 1982169113. The next prime is 1982169131. The reversal of 1982169121 is 1219612891.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1431562896 + 550606225 = 37836^2 + 23465^2 .

It is a cyclic number.

It is not a de Polignac number, because 1982169121 - 2³ = 1982169113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1982169131) 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, 147930 + ... + 160771.

It is an arithmetic number, because the mean of its divisors is an integer number (495621061).

Almost surely, 2^1982169121 is an apocalyptic number.

It is an amenable number.

1982169121 is a deficient number, since it is larger than the sum of its proper divisors (315123).

1982169121 is an equidigital number, since it uses as much as digits as its factorization.

1982169121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315122.

The product of its digits is 15552, while the sum is 40.

The square root of 1982169121 is about 44521.5579354541. The cubic root of 1982169121 is about 1256.1656172754.

The spelling of 1982169121 in words is "one billion, nine hundred eighty-two million, one hundred sixty-nine thousand, one hundred twenty-one".