81003646 has 8 divisors (see below), whose sum is σ = 121552200. Its totient is φ = 40486248.

The previous prime is 81003613. The next prime is 81003649. The reversal of 81003646 is 64630018.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81003649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 460 + ... + 12736.

It is an arithmetic number, because the mean of its divisors is an integer number (15194025).

Almost surely, 2^81003646 is an apocalyptic number.

81003646 is a deficient number, since it is larger than the sum of its proper divisors (40548554).

81003646 is a wasteful number, since it uses less digits than its factorization.

81003646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15578.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 81003646 is about 9000.2025532762. The cubic root of 81003646 is about 432.6813628984.

The spelling of 81003646 in words is "eighty-one million, three thousand, six hundred forty-six".