81130165 has 8 divisors (see below), whose sum is σ = 97413120. Its totient is φ = 64866192.

The previous prime is 81130163. The next prime is 81130187. The reversal of 81130165 is 56103118.

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 81130165 - 2¹ = 81130163 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81130163) 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, 7572 + ... + 14818.

It is an arithmetic number, because the mean of its divisors is an integer number (12176640).

Almost surely, 2^81130165 is an apocalyptic number.

It is an amenable number.

81130165 is a deficient number, since it is larger than the sum of its proper divisors (16282955).

81130165 is a wasteful number, since it uses less digits than its factorization.

81130165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9491.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 81130165 is about 9007.2284860550. The cubic root of 81130165 is about 432.9065130004.

It can be divided in two parts, 811 and 30165, that added together give a square (30976 = 176²).

The spelling of 81130165 in words is "eighty-one million, one hundred thirty thousand, one hundred sixty-five".