81370 has 16 divisors (see below), whose sum is σ = 149760. Its totient is φ = 31824.

The previous prime is 81359. The next prime is 81371. The reversal of 81370 is 7318.

81370 = 3² + 4² + ... + 62².

It is an Ulam number.

81370 is a Rhonda number in base 8.

It is not an unprimeable number, because it can be changed into a prime (81371) 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, 739 + ... + 841.

It is an arithmetic number, because the mean of its divisors is an integer number (9360).

2⁸¹³⁷⁰ is an apocalyptic number.

81370 is a deficient number, since it is larger than the sum of its proper divisors (68390).

81370 is a wasteful number, since it uses less digits than its factorization.

81370 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189.

The product of its (nonzero) digits is 168, while the sum is 19.

The square root of 81370 is about 285.2542725359. The cubic root of 81370 is about 43.3332675870. Note that the first 3 decimals are identical.

Adding to 81370 its reverse (7318), we get a palindrome (88688).

It can be divided in two parts, 8 and 1370, that added together give a triangular number (1378 = T₅₂).

The spelling of 81370 in words is "eighty-one thousand, three hundred seventy".