81535260 has 48 divisors (see below), whose sum is σ = 229211136. Its totient is φ = 21655872.

The previous prime is 81535249. The next prime is 81535261. The reversal of 81535260 is 6253518.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81535261) 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 15 ways as a sum of consecutive naturals, for example, 13197 + ... + 18363.

It is an arithmetic number, because the mean of its divisors is an integer number (4775232).

Almost surely, 2^81535260 is an apocalyptic number.

It is an amenable number.

81535260 is an abundant number, since it is smaller than the sum of its proper divisors (147675876).

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

81535260 is a wasteful number, since it uses less digits than its factorization.

81535260 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5442 (or 5440 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 30.

The square root of 81535260 is about 9029.6877022409. The cubic root of 81535260 is about 433.6258393279.

Adding to 81535260 its reverse (6253518), we get a palindrome (87788778).

The spelling of 81535260 in words is "eighty-one million, five hundred thirty-five thousand, two hundred sixty".