1981609533039 has 8 divisors (see below), whose sum is σ = 2781206362240. Its totient is φ = 1251542862936.

The previous prime is 1981609533031. The next prime is 1981609533097. The reversal of 1981609533039 is 9303359061891.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1981609533039 - 2³ = 1981609533031 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57), and also a Moran number because the ratio is a prime number: 34765079527 = 1981609533039 / (1 + 9 + 8 + 1 + 6 + 0 + 9 + 5 + 3 + 3 + 0 + 3 + 9).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1981609533039.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1981609533031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17382539707 + ... + 17382539820.

It is an arithmetic number, because the mean of its divisors is an integer number (347650795280).

Almost surely, 2^{1981609533039} is an apocalyptic number.

1981609533039 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

1981609533039 is a deficient number, since it is larger than the sum of its proper divisors (799596829201).

1981609533039 is a wasteful number, since it uses less digits than its factorization.

1981609533039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34765079549.

The product of its (nonzero) digits is 4723920, while the sum is 57.

The spelling of 1981609533039 in words is "one trillion, nine hundred eighty-one billion, six hundred nine million, five hundred thirty-three thousand, thirty-nine".