81173677 has 8 divisors (see below), whose sum is σ = 87873464. Its totient is φ = 74539008.

The previous prime is 81173669. The next prime is 81173689. The reversal of 81173677 is 77637118.

It can be written as a sum of positive squares in 4 ways, for example, as 6022116 + 75151561 = 2454^2 + 8669^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81173677 - 2³ = 81173669 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81173627) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13668 + ... + 18685.

It is an arithmetic number, because the mean of its divisors is an integer number (10984183).

Almost surely, 2^81173677 is an apocalyptic number.

It is an amenable number.

81173677 is a deficient number, since it is larger than the sum of its proper divisors (6699787).

81173677 is a wasteful number, since it uses less digits than its factorization.

81173677 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32559.

The product of its digits is 49392, while the sum is 40.

The square root of 81173677 is about 9009.6435556575. The cubic root of 81173677 is about 432.9838917891.

The spelling of 81173677 in words is "eighty-one million, one hundred seventy-three thousand, six hundred seventy-seven".