81336433 has 4 divisors (see below), whose sum is σ = 81355428. Its totient is φ = 81317440.

The previous prime is 81336427. The next prime is 81336439. The reversal of 81336433 is 33463318.

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

It is an interprime number because it is at equal distance from previous prime (81336427) and next prime (81336439).

It can be written as a sum of positive squares in 2 ways, for example, as 67371264 + 13965169 = 8208^2 + 3737^2 .

It is a cyclic number.

It is not a de Polignac number, because 81336433 - 2⁵ = 81336401 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81336395 and 81336404.

It is not an unprimeable number, because it can be changed into a prime (81336439) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 285 + ... + 12757.

It is an arithmetic number, because the mean of its divisors is an integer number (20338857).

Almost surely, 2^81336433 is an apocalyptic number.

It is an amenable number.

81336433 is a deficient number, since it is larger than the sum of its proper divisors (18995).

81336433 is a wasteful number, since it uses less digits than its factorization.

81336433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18994.

The product of its digits is 15552, while the sum is 31.

The square root of 81336433 is about 9018.6713544735. The cubic root of 81336433 is about 433.2730811033.

The spelling of 81336433 in words is "eighty-one million, three hundred thirty-six thousand, four hundred thirty-three".