81362170 has 48 divisors (see below), whose sum is σ = 159148800. Its totient is φ = 29928704.

The previous prime is 81362167. The next prime is 81362189. The reversal of 81362170 is 7126318.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 135531 + ... + 136129.

It is an arithmetic number, because the mean of its divisors is an integer number (3315600).

Almost surely, 2^81362170 is an apocalyptic number.

81362170 is a deficient number, since it is larger than the sum of its proper divisors (77786630).

81362170 is a wasteful number, since it uses less digits than its factorization.

81362170 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 687 (or 670 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 81362170 is about 9020.0981147657. The cubic root of 81362170 is about 433.3187759738.

Adding to 81362170 its reverse (7126318), we get a palindrome (88488488).

The spelling of 81362170 in words is "eighty-one million, three hundred sixty-two thousand, one hundred seventy".