81853524 has 24 divisors (see below), whose sum is σ = 212213120. Its totient is φ = 27284472.

The previous prime is 81853517. The next prime is 81853529. The reversal of 81853524 is 42535818.

It is a happy number.

81853524 is a `hidden beast` number, since 81 + 8 + 53 + 524 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81853529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 378844 + ... + 379059.

Almost surely, 2^81853524 is an apocalyptic number.

It is an amenable number.

81853524 is an abundant number, since it is smaller than the sum of its proper divisors (130359596).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81853524 is a wasteful number, since it uses less digits than its factorization.

81853524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 757916 (or 757908 counting only the distinct ones).

The product of its digits is 38400, while the sum is 36.

The square root of 81853524 is about 9047.2937390139. The cubic root of 81853524 is about 434.1893105458.

The spelling of 81853524 in words is "eighty-one million, eight hundred fifty-three thousand, five hundred twenty-four".