1978544329 has 4 divisors (see below), whose sum is σ = 1991823300. Its totient is φ = 1965265360.

The previous prime is 1978544317. The next prime is 1978544353. The reversal of 1978544329 is 9234458791.

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 142850304 + 1835694025 = 11952^2 + 42845^2 .

It is a cyclic number.

It is not a de Polignac number, because 1978544329 - 2⁵ = 1978544297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1978544629) 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, 6639262 + ... + 6639559.

It is an arithmetic number, because the mean of its divisors is an integer number (497955825).

Almost surely, 2^1978544329 is an apocalyptic number.

It is an amenable number.

1978544329 is a deficient number, since it is larger than the sum of its proper divisors (13278971).

1978544329 is a wasteful number, since it uses less digits than its factorization.

1978544329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13278970.

The product of its digits is 2177280, while the sum is 52.

The square root of 1978544329 is about 44480.8310286577. The cubic root of 1978544329 is about 1255.3994334992.

The spelling of 1978544329 in words is "one billion, nine hundred seventy-eight million, five hundred forty-four thousand, three hundred twenty-nine".