81737443 has 4 divisors (see below), whose sum is σ = 82857208. Its totient is φ = 80617680.

The previous prime is 81737431. The next prime is 81737473. The reversal of 81737443 is 34473718.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81737443 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81737413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 559773 + ... + 559918.

It is an arithmetic number, because the mean of its divisors is an integer number (20714302).

Almost surely, 2^81737443 is an apocalyptic number.

81737443 is a deficient number, since it is larger than the sum of its proper divisors (1119765).

81737443 is a wasteful number, since it uses less digits than its factorization.

81737443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1119764.

The product of its digits is 56448, while the sum is 37.

The square root of 81737443 is about 9040.8762296583. The cubic root of 81737443 is about 433.9839641693.

The spelling of 81737443 in words is "eighty-one million, seven hundred thirty-seven thousand, four hundred forty-three".