81733018 has 4 divisors (see below), whose sum is σ = 122599530. Its totient is φ = 40866508.

The previous prime is 81732997. The next prime is 81733027. The reversal of 81733018 is 81033718.

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

It can be written as a sum of positive squares in only one way, i.e., 60637369 + 21095649 = 7787^2 + 4593^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20433253 + ... + 20433256.

Almost surely, 2^81733018 is an apocalyptic number.

81733018 is a deficient number, since it is larger than the sum of its proper divisors (40866512).

81733018 is a wasteful number, since it uses less digits than its factorization.

81733018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40866511.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 81733018 is about 9040.6315044913. The cubic root of 81733018 is about 433.9761325333.

The spelling of 81733018 in words is "eighty-one million, seven hundred thirty-three thousand, eighteen".