81906083 has 8 divisors (see below), whose sum is σ = 93767520. Its totient is φ = 70084800.

The previous prime is 81906067. The next prime is 81906107. The reversal of 81906083 is 38060918.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81906083 - 2⁴ = 81906067 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81906023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5528 + ... + 13941.

It is an arithmetic number, because the mean of its divisors is an integer number (11720940).

Almost surely, 2^81906083 is an apocalyptic number.

81906083 is a deficient number, since it is larger than the sum of its proper divisors (11861437).

81906083 is a wasteful number, since it uses less digits than its factorization.

81906083 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20077.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 81906083 is about 9050.1979536362. The cubic root of 81906083 is about 434.2822231543.

It can be divided in two parts, 8 and 1906083, that added together give a palindrome (1906091).

The spelling of 81906083 in words is "eighty-one million, nine hundred six thousand, eighty-three".