81750365 has 8 divisors (see below), whose sum is σ = 103871160. Its totient is φ = 61553152.

The previous prime is 81750359. The next prime is 81750367. The reversal of 81750365 is 56305718.

It can be written as a sum of positive squares in 4 ways, for example, as 44063044 + 37687321 = 6638^2 + 6139^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 81750365 - 2¹⁰ = 81749341 is a prime.

It is a super-3 number, since 3×81750365³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81750367) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 480800 + ... + 480969.

It is an arithmetic number, because the mean of its divisors is an integer number (12983895).

Almost surely, 2^81750365 is an apocalyptic number.

81750365 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

It is an amenable number.

81750365 is a deficient number, since it is larger than the sum of its proper divisors (22120795).

81750365 is a wasteful number, since it uses less digits than its factorization.

81750365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 961791.

The product of its (nonzero) digits is 25200, while the sum is 35.

The square root of 81750365 is about 9041.5908445362. The cubic root of 81750365 is about 434.0068326984.

The spelling of 81750365 in words is "eighty-one million, seven hundred fifty thousand, three hundred sixty-five".