81363694 has 4 divisors (see below), whose sum is σ = 122045544. Its totient is φ = 40681846.

The previous prime is 81363677. The next prime is 81363713. The reversal of 81363694 is 49636318.

It is a semiprime because it is the product of two primes.

It is a super-3 number, since 3×81363694³ (a number of 25 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20340922 + ... + 20340925.

It is an arithmetic number, because the mean of its divisors is an integer number (30511386).

Almost surely, 2^81363694 is an apocalyptic number.

81363694 is a deficient number, since it is larger than the sum of its proper divisors (40681850).

81363694 is a wasteful number, since it uses less digits than its factorization.

81363694 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40681849.

The product of its digits is 93312, while the sum is 40.

The square root of 81363694 is about 9020.1825923869. The cubic root of 81363694 is about 433.3214814641.

The spelling of 81363694 in words is "eighty-one million, three hundred sixty-three thousand, six hundred ninety-four".