81484729 has 4 divisors (see below), whose sum is σ = 81894400. Its totient is φ = 81075060.

The previous prime is 81484721. The next prime is 81484747. The reversal of 81484729 is 92748418.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81484729 - 2³ = 81484721 is a prime.

It is a super-2 number, since 2×81484729² = 13279522120406882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81484721) 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, 204537 + ... + 204934.

It is an arithmetic number, because the mean of its divisors is an integer number (20473600).

Almost surely, 2^81484729 is an apocalyptic number.

It is an amenable number.

81484729 is a deficient number, since it is larger than the sum of its proper divisors (409671).

81484729 is a wasteful number, since it uses less digits than its factorization.

81484729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 409670.

The product of its digits is 129024, while the sum is 43.

The square root of 81484729 is about 9026.8892205455. The cubic root of 81484729 is about 433.5362417911.

The spelling of 81484729 in words is "eighty-one million, four hundred eighty-four thousand, seven hundred twenty-nine".