81193406 has 8 divisors (see below), whose sum is σ = 139188720. Its totient is φ = 34797168.

The previous prime is 81193369. The next prime is 81193421. The reversal of 81193406 is 60439118.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2899751 + ... + 2899778.

It is an arithmetic number, because the mean of its divisors is an integer number (17398590).

Almost surely, 2^81193406 is an apocalyptic number.

81193406 is a deficient number, since it is larger than the sum of its proper divisors (57995314).

81193406 is a wasteful number, since it uses less digits than its factorization.

81193406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5799538.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 81193406 is about 9010.7383715209. The cubic root of 81193406 is about 433.0189673930.

The spelling of 81193406 in words is "eighty-one million, one hundred ninety-three thousand, four hundred six".