81627473 has 4 divisors (see below), whose sum is σ = 83167668. Its totient is φ = 80087280.

The previous prime is 81627467. The next prime is 81627487. The reversal of 81627473 is 37472618.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 37472618 = 2 ⋅18736309.

It can be written as a sum of positive squares in 2 ways, for example, as 51509329 + 30118144 = 7177^2 + 5488^2 .

It is a cyclic number.

It is not a de Polignac number, because 81627473 - 2⁴ = 81627457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81627463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 770018 + ... + 770123.

It is an arithmetic number, because the mean of its divisors is an integer number (20791917).

Almost surely, 2^81627473 is an apocalyptic number.

It is an amenable number.

81627473 is a deficient number, since it is larger than the sum of its proper divisors (1540195).

81627473 is a wasteful number, since it uses less digits than its factorization.

81627473 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1540194.

The product of its digits is 56448, while the sum is 38.

The square root of 81627473 is about 9034.7923606467. The cubic root of 81627473 is about 433.7892486914.

The spelling of 81627473 in words is "eighty-one million, six hundred twenty-seven thousand, four hundred seventy-three".