81906926 has 4 divisors (see below), whose sum is σ = 122860392. Its totient is φ = 40953462.

The previous prime is 81906917. The next prime is 81906941. The reversal of 81906926 is 62960918.

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

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, 20476730 + ... + 20476733.

It is an arithmetic number, because the mean of its divisors is an integer number (30715098).

Almost surely, 2^81906926 is an apocalyptic number.

81906926 is a deficient number, since it is larger than the sum of its proper divisors (40953466).

81906926 is a wasteful number, since it uses less digits than its factorization.

81906926 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40953465.

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 81906926 is about 9050.2445270832. The cubic root of 81906926 is about 434.2837130666.

The spelling of 81906926 in words is "eighty-one million, nine hundred six thousand, nine hundred twenty-six".