81996206 has 4 divisors (see below), whose sum is σ = 122994312. Its totient is φ = 40998102.

The previous prime is 81996203. The next prime is 81996221. The reversal of 81996206 is 60269918.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81996203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20499050 + ... + 20499053.

It is an arithmetic number, because the mean of its divisors is an integer number (30748578).

Almost surely, 2^81996206 is an apocalyptic number.

81996206 is a deficient number, since it is larger than the sum of its proper divisors (40998106).

81996206 is a wasteful number, since it uses less digits than its factorization.

81996206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40998105.

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

The square root of 81996206 is about 9055.1756471092. The cubic root of 81996206 is about 434.4414480822.

The spelling of 81996206 in words is "eighty-one million, nine hundred ninety-six thousand, two hundred six".