81137170 has 16 divisors (see below), whose sum is σ = 148803480. Its totient is φ = 31842304.

The previous prime is 81137159. The next prime is 81137179. The reversal of 81137170 is 7173118.

It can be written as a sum of positive squares in 4 ways, for example, as 79014321 + 2122849 = 8889^2 + 1457^2 .

It is not an unprimeable number, because it can be changed into a prime (81137179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76015 + ... + 77074.

Almost surely, 2^81137170 is an apocalyptic number.

81137170 is a deficient number, since it is larger than the sum of its proper divisors (67666310).

81137170 is a wasteful number, since it uses less digits than its factorization.

81137170 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153149.

The product of its (nonzero) digits is 1176, while the sum is 28.

The square root of 81137170 is about 9007.6173320141. The cubic root of 81137170 is about 432.9189720853.

The spelling of 81137170 in words is "eighty-one million, one hundred thirty-seven thousand, one hundred seventy".