982121809 has 4 divisors (see below), whose sum is σ = 987264000. Its totient is φ = 976979620.

The previous prime is 982121737. The next prime is 982121839. The reversal of 982121809 is 908121289.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 908121289 = 24611 ⋅36899.

It is a cyclic number.

It is not a de Polignac number, because 982121809 - 2¹⁵ = 982089041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (982121839) 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, 2570809 + ... + 2571190.

It is an arithmetic number, because the mean of its divisors is an integer number (246816000).

Almost surely, 2^982121809 is an apocalyptic number.

It is an amenable number.

982121809 is a deficient number, since it is larger than the sum of its proper divisors (5142191).

982121809 is a wasteful number, since it uses less digits than its factorization.

982121809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5142190.

The product of its (nonzero) digits is 20736, while the sum is 40.

The square root of 982121809 is about 31338.8227124122. The cubic root of 982121809 is about 994.0047315864.

The spelling of 982121809 in words is "nine hundred eighty-two million, one hundred twenty-one thousand, eight hundred nine".