81696494 has 8 divisors (see below), whose sum is σ = 133685208. Its totient is φ = 37134760.

The previous prime is 81696493. The next prime is 81696497. The reversal of 81696494 is 49469618.

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 not an unprimeable number, because it can be changed into a prime (81696493) by changing a digit.

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, 1856717 + ... + 1856760.

It is an arithmetic number, because the mean of its divisors is an integer number (16710651).

Almost surely, 2^81696494 is an apocalyptic number.

81696494 is a deficient number, since it is larger than the sum of its proper divisors (51988714).

81696494 is a wasteful number, since it uses less digits than its factorization.

81696494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3713490.

The product of its digits is 373248, while the sum is 47.

The square root of 81696494 is about 9038.6112871392. The cubic root of 81696494 is about 433.9114793234.

The spelling of 81696494 in words is "eighty-one million, six hundred ninety-six thousand, four hundred ninety-four".