81481305 has 8 divisors (see below), whose sum is σ = 130370112. Its totient is φ = 43456688.

The previous prime is 81481303. The next prime is 81481307. The reversal of 81481305 is 50318418.

It is an interprime number because it is at equal distance from previous prime (81481303) and next prime (81481307).

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 81481305 - 2¹ = 81481303 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81481303) 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, 2716029 + ... + 2716058.

It is an arithmetic number, because the mean of its divisors is an integer number (16296264).

Almost surely, 2^81481305 is an apocalyptic number.

It is an amenable number.

81481305 is a deficient number, since it is larger than the sum of its proper divisors (48888807).

81481305 is a wasteful number, since it uses less digits than its factorization.

81481305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5432095.

The product of its (nonzero) digits is 3840, while the sum is 30.

The square root of 81481305 is about 9026.6995629632. The cubic root of 81481305 is about 433.5301692877.

It can be divided in two parts, 8148 and 1305, that added together give a triangular number (9453 = T₁₃₇).

The spelling of 81481305 in words is "eighty-one million, four hundred eighty-one thousand, three hundred five".