81827461 has 8 divisors (see below), whose sum is σ = 84177144. Its totient is φ = 79485120.

The previous prime is 81827441. The next prime is 81827479. The reversal of 81827461 is 16472818.

It can be written as a sum of positive squares in 4 ways, for example, as 11519236 + 70308225 = 3394^2 + 8385^2 .

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 81827461 - 2¹¹ = 81825413 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81827461.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81827441) 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, 27171 + ... + 30031.

It is an arithmetic number, because the mean of its divisors is an integer number (10522143).

Almost surely, 2^81827461 is an apocalyptic number.

It is an amenable number.

81827461 is a deficient number, since it is larger than the sum of its proper divisors (2349683).

81827461 is a wasteful number, since it uses less digits than its factorization.

81827461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3671.

The product of its digits is 21504, while the sum is 37.

The square root of 81827461 is about 9045.8532488649. The cubic root of 81827461 is about 434.1432222134.

The spelling of 81827461 in words is "eighty-one million, eight hundred twenty-seven thousand, four hundred sixty-one".