81390603 has 8 divisors (see below), whose sum is σ = 124023808. Its totient is φ = 46508904.

The previous prime is 81390571. The next prime is 81390607. The reversal of 81390603 is 30609318.

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

It is not a de Polignac number, because 81390603 - 2⁵ = 81390571 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81390607) 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, 1937851 + ... + 1937892.

It is an arithmetic number, because the mean of its divisors is an integer number (15502976).

Almost surely, 2^81390603 is an apocalyptic number.

81390603 is a deficient number, since it is larger than the sum of its proper divisors (42633205).

81390603 is a wasteful number, since it uses less digits than its factorization.

81390603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3875753.

The product of its (nonzero) digits is 3888, while the sum is 30.

The square root of 81390603 is about 9021.6740685972. The cubic root of 81390603 is about 433.3692462675.

The spelling of 81390603 in words is "eighty-one million, three hundred ninety thousand, six hundred three".