81012170 has 8 divisors (see below), whose sum is σ = 145821924. Its totient is φ = 32404864.

The previous prime is 81012163. The next prime is 81012193. The reversal of 81012170 is 7121018.

It can be written as a sum of positive squares in 2 ways, for example, as 70778569 + 10233601 = 8413^2 + 3199^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4050599 + ... + 4050618.

Almost surely, 2^81012170 is an apocalyptic number.

81012170 is a deficient number, since it is larger than the sum of its proper divisors (64809754).

81012170 is a wasteful number, since it uses less digits than its factorization.

81012170 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8101224.

The product of its (nonzero) digits is 112, while the sum is 20.

The square root of 81012170 is about 9000.6760857171. The cubic root of 81012170 is about 432.6965393617.

Adding to 81012170 its reverse (7121018), we get a palindrome (88133188).

The spelling of 81012170 in words is "eighty-one million, twelve thousand, one hundred seventy".