81485761 has 8 divisors (see below), whose sum is σ = 93545984. Its totient is φ = 69530400.

The previous prime is 81485759. The next prime is 81485771. The reversal of 81485761 is 16758418.

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 81485761 - 2¹ = 81485759 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81485771) 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, 24540 + ... + 27661.

It is an arithmetic number, because the mean of its divisors is an integer number (11693248).

Almost surely, 2^81485761 is an apocalyptic number.

It is an amenable number.

81485761 is a deficient number, since it is larger than the sum of its proper divisors (12060223).

81485761 is a wasteful number, since it uses less digits than its factorization.

81485761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52431.

The product of its digits is 53760, while the sum is 40.

The square root of 81485761 is about 9026.9463829138. The cubic root of 81485761 is about 433.5380720216.

The spelling of 81485761 in words is "eighty-one million, four hundred eighty-five thousand, seven hundred sixty-one".