81130071 has 8 divisors (see below), whose sum is σ = 118007424. Its totient is φ = 49169720.

The previous prime is 81130043. The next prime is 81130073. The reversal of 81130071 is 17003118.

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 81130071 - 2¹³ = 81121879 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81130073) 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, 1229211 + ... + 1229276.

It is an arithmetic number, because the mean of its divisors is an integer number (14750928).

Almost surely, 2^81130071 is an apocalyptic number.

81130071 is a deficient number, since it is larger than the sum of its proper divisors (36877353).

81130071 is a wasteful number, since it uses less digits than its factorization.

81130071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2458501.

The product of its (nonzero) digits is 168, while the sum is 21.

The square root of 81130071 is about 9007.2232680222. The cubic root of 81130071 is about 432.9063458072.

Adding to 81130071 its reverse (17003118), we get a palindrome (98133189).

The spelling of 81130071 in words is "eighty-one million, one hundred thirty thousand, seventy-one".