81758396 has 6 divisors (see below), whose sum is σ = 143077200. Its totient is φ = 40879196.

The previous prime is 81758381. The next prime is 81758401. The reversal of 81758396 is 69385718.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 81758396.

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, 10219796 + ... + 10219803.

It is an arithmetic number, because the mean of its divisors is an integer number (23846200).

Almost surely, 2^81758396 is an apocalyptic number.

It is an amenable number.

81758396 is a deficient number, since it is larger than the sum of its proper divisors (61318804).

81758396 is a wasteful number, since it uses less digits than its factorization.

81758396 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20439603 (or 20439601 counting only the distinct ones).

The product of its digits is 362880, while the sum is 47.

The square root of 81758396 is about 9042.0349479528. The cubic root of 81758396 is about 434.0210442343.

The spelling of 81758396 in words is "eighty-one million, seven hundred fifty-eight thousand, three hundred ninety-six".