81385603 has 8 divisors (see below), whose sum is σ = 89132400. Its totient is φ = 73851168.

The previous prime is 81385589. The next prime is 81385631. The reversal of 81385603 is 30658318.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 81385603 - 2⁹ = 81385091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81385663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52288 + ... + 53821.

It is an arithmetic number, because the mean of its divisors is an integer number (11141550).

Almost surely, 2^81385603 is an apocalyptic number.

81385603 is a deficient number, since it is larger than the sum of its proper divisors (7746797).

81385603 is a wasteful number, since it uses less digits than its factorization.

81385603 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106181.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 81385603 is about 9021.3969539091. The cubic root of 81385603 is about 433.3603718171.

The spelling of 81385603 in words is "eighty-one million, three hundred eighty-five thousand, six hundred three".