81369875 has 16 divisors (see below), whose sum is σ = 106897440. Its totient is φ = 61668000.

The previous prime is 81369851. The next prime is 81369877. The reversal of 81369875 is 57896318.

It is a happy number.

It is not a de Polignac number, because 81369875 - 2⁶ = 81369811 is a prime.

It is a super-3 number, since 3×81369875³ (a number of 25 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (81369877) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14756 + ... + 19505.

It is an arithmetic number, because the mean of its divisors is an integer number (6681090).

Almost surely, 2^81369875 is an apocalyptic number.

81369875 is a deficient number, since it is larger than the sum of its proper divisors (25527565).

81369875 is a wasteful number, since it uses less digits than its factorization.

81369875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34295 (or 34285 counting only the distinct ones).

The product of its digits is 362880, while the sum is 47.

The square root of 81369875 is about 9020.5252064389. The cubic root of 81369875 is about 433.3324539759.

The spelling of 81369875 in words is "eighty-one million, three hundred sixty-nine thousand, eight hundred seventy-five".