81384878479 has 8 divisors (see below), whose sum is σ = 81992465840. Its totient is φ = 80778612096.

The previous prime is 81384878437. The next prime is 81384878489. The reversal of 81384878479 is 97487848318.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81384878479 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81384878489) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 206394 + ... + 453175.

It is an arithmetic number, because the mean of its divisors is an integer number (10249058230).

Almost surely, 2^81384878479 is an apocalyptic number.

81384878479 is a deficient number, since it is larger than the sum of its proper divisors (607587361).

81384878479 is a wasteful number, since it uses less digits than its factorization.

81384878479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 660489.

The product of its digits is 86704128, while the sum is 67.

The spelling of 81384878479 in words is "eighty-one billion, three hundred eighty-four million, eight hundred seventy-eight thousand, four hundred seventy-nine".