1984121919 has 32 divisors (see below), whose sum is σ = 3169510400. Its totient is φ = 1219471200.

The previous prime is 1984121891. The next prime is 1984121921. The reversal of 1984121919 is 9191214891.

It is a happy number.

It is not a de Polignac number, because 1984121919 - 2²⁰ = 1983073343 is a prime.

It is a super-2 number, since 2×1984121919² = 7873479578912485122, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1984121959) 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 31 ways as a sum of consecutive naturals, for example, 319494 + ... + 325644.

It is an arithmetic number, because the mean of its divisors is an integer number (99047200).

Almost surely, 2^1984121919 is an apocalyptic number.

1984121919 is a deficient number, since it is larger than the sum of its proper divisors (1185388481).

1984121919 is a wasteful number, since it uses less digits than its factorization.

1984121919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7092 (or 7086 counting only the distinct ones).

The product of its digits is 46656, while the sum is 45.

The square root of 1984121919 is about 44543.4834627917. The cubic root of 1984121919 is about 1256.5779992726.

The spelling of 1984121919 in words is "one billion, nine hundred eighty-four million, one hundred twenty-one thousand, nine hundred nineteen".