81284589 has 12 divisors (see below), whose sum is σ = 117832572. Its totient is φ = 53995200.

The previous prime is 81284579. The next prime is 81284627. The reversal of 81284589 is 98548218.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 71267364 + 10017225 = 8442^2 + 3165^2 .

It is not a de Polignac number, because 81284589 - 2²³ = 72895981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81284519) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13542 + ... + 18599.

It is an arithmetic number, because the mean of its divisors is an integer number (9819381).

Almost surely, 2^81284589 is an apocalyptic number.

It is an amenable number.

81284589 is a deficient number, since it is larger than the sum of its proper divisors (36547983).

81284589 is a wasteful number, since it uses less digits than its factorization.

81284589 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32428 (or 32425 counting only the distinct ones).

The product of its digits is 184320, while the sum is 45.

The square root of 81284589 is about 9015.7966370144. The cubic root of 81284589 is about 433.1810051703.

The spelling of 81284589 in words is "eighty-one million, two hundred eighty-four thousand, five hundred eighty-nine".