81758936 has 32 divisors (see below), whose sum is σ = 176010240. Its totient is φ = 34877088.

The previous prime is 81758927. The next prime is 81758939. The reversal of 81758936 is 63985718.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81758939) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9215 + ... + 15761.

It is an arithmetic number, because the mean of its divisors is an integer number (5500320).

Almost surely, 2^81758936 is an apocalyptic number.

It is an amenable number.

81758936 is an abundant number, since it is smaller than the sum of its proper divisors (94251304).

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

81758936 is a wasteful number, since it uses less digits than its factorization.

81758936 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6783 (or 6779 counting only the distinct ones).

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

The square root of 81758936 is about 9042.0648084384. The cubic root of 81758936 is about 434.0219997767.

The spelling of 81758936 in words is "eighty-one million, seven hundred fifty-eight thousand, nine hundred thirty-six".