81704473 has 4 divisors (see below), whose sum is σ = 83912740. Its totient is φ = 79496208.

The previous prime is 81704461. The next prime is 81704489. The reversal of 81704473 is 37440718.

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

It can be written as a sum of positive squares in 2 ways, for example, as 71031184 + 10673289 = 8428^2 + 3267^2 .

It is a cyclic number.

It is not a de Polignac number, because 81704473 - 2⁹ = 81703961 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81705473) 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, 1104078 + ... + 1104151.

It is an arithmetic number, because the mean of its divisors is an integer number (20978185).

Almost surely, 2^81704473 is an apocalyptic number.

It is an amenable number.

81704473 is a deficient number, since it is larger than the sum of its proper divisors (2208267).

81704473 is a wasteful number, since it uses less digits than its factorization.

81704473 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2208266.

The product of its (nonzero) digits is 18816, while the sum is 34.

The square root of 81704473 is about 9039.0526605392. The cubic root of 81704473 is about 433.9256050499.

The spelling of 81704473 in words is "eighty-one million, seven hundred four thousand, four hundred seventy-three".