81529530 has 16 divisors (see below), whose sum is σ = 195670944. Its totient is φ = 21741200.

The previous prime is 81529519. The next prime is 81529531. The reversal of 81529530 is 3592518.

It is a junction number, because it is equal to n+sod(n) for n = 81529491 and 81529500.

It is not an unprimeable number, because it can be changed into a prime (81529531) 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, 1358796 + ... + 1358855.

It is an arithmetic number, because the mean of its divisors is an integer number (12229434).

Almost surely, 2^81529530 is an apocalyptic number.

81529530 is an abundant number, since it is smaller than the sum of its proper divisors (114141414).

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

81529530 is a wasteful number, since it uses less digits than its factorization.

81529530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2717661.

The product of its (nonzero) digits is 10800, while the sum is 33.

The square root of 81529530 is about 9029.3704099455. The cubic root of 81529530 is about 433.6156812103.

The spelling of 81529530 in words is "eighty-one million, five hundred twenty-nine thousand, five hundred thirty".