81645083 has 12 divisors (see below), whose sum is σ = 88696440. Its totient is φ = 75119616.

The previous prime is 81645079. The next prime is 81645097. The reversal of 81645083 is 38054618.

It is not a de Polignac number, because 81645083 - 2² = 81645079 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81645073) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 70235 + ... + 71387.

It is an arithmetic number, because the mean of its divisors is an integer number (7391370).

Almost surely, 2^81645083 is an apocalyptic number.

81645083 is a deficient number, since it is larger than the sum of its proper divisors (7051357).

81645083 is a wasteful number, since it uses less digits than its factorization.

81645083 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1598 (or 1585 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 35.

The square root of 81645083 is about 9035.7668739294. The cubic root of 81645083 is about 433.8204411283.

The spelling of 81645083 in words is "eighty-one million, six hundred forty-five thousand, eighty-three".