81193506 has 8 divisors (see below), whose sum is σ = 162387024. Its totient is φ = 27064500.

The previous prime is 81193493. The next prime is 81193531. The reversal of 81193506 is 60539118.

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

81193506 is an admirable number.

It is a Curzon number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 6766120 + ... + 6766131.

It is an arithmetic number, because the mean of its divisors is an integer number (20298378).

Almost surely, 2^81193506 is an apocalyptic number.

81193506 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81193506 is a wasteful number, since it uses less digits than its factorization.

81193506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13532256.

The product of its (nonzero) digits is 6480, while the sum is 33.

The square root of 81193506 is about 9010.7439204541. The cubic root of 81193506 is about 433.0191451656.

The spelling of 81193506 in words is "eighty-one million, one hundred ninety-three thousand, five hundred six".