81030385639 has 8 divisors (see below), whose sum is σ = 94759786880. Its totient is φ = 67839392376.

The previous prime is 81030385621. The next prime is 81030385643. The reversal of 81030385639 is 93658303018.

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

It is not a de Polignac number, because 81030385639 - 2⁹ = 81030385127 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 (81030385649) 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, 134601669 + ... + 134602270.

It is an arithmetic number, because the mean of its divisors is an integer number (11844973360).

Almost surely, 2^81030385639 is an apocalyptic number.

81030385639 is a deficient number, since it is larger than the sum of its proper divisors (13729401241).

81030385639 is a wasteful number, since it uses less digits than its factorization.

81030385639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269203989.

The product of its (nonzero) digits is 466560, while the sum is 46.

The spelling of 81030385639 in words is "eighty-one billion, thirty million, three hundred eighty-five thousand, six hundred thirty-nine".