81208033 has 12 divisors (see below), whose sum is σ = 88673940. Its totient is φ = 74271456.

The previous prime is 81208027. The next prime is 81208051. The reversal of 81208033 is 33080218.

It can be written as a sum of positive squares in 2 ways, for example, as 55472704 + 25735329 = 7448^2 + 5073^2 .

It is not a de Polignac number, because 81208033 - 2²¹ = 79110881 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81207989 and 81208007.

It is not an unprimeable number, because it can be changed into a prime (81208073) 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 11 ways as a sum of consecutive naturals, for example, 6591 + ... + 14347.

It is an arithmetic number, because the mean of its divisors is an integer number (7389495).

Almost surely, 2^81208033 is an apocalyptic number.

It is an amenable number.

81208033 is a deficient number, since it is larger than the sum of its proper divisors (7465907).

81208033 is a wasteful number, since it uses less digits than its factorization.

81208033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7824 (or 7805 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 81208033 is about 9011.5499776675. The cubic root of 81208033 is about 433.0449686348.

The spelling of 81208033 in words is "eighty-one million, two hundred eight thousand, thirty-three".