81530016 has 24 divisors (see below), whose sum is σ = 214016544. Its totient is φ = 27176640.

The previous prime is 81529993. The next prime is 81530051. The reversal of 81530016 is 61003518.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 424540 + ... + 424731.

It is an arithmetic number, because the mean of its divisors is an integer number (8917356).

Almost surely, 2^81530016 is an apocalyptic number.

It is an amenable number.

81530016 is an abundant number, since it is smaller than the sum of its proper divisors (132486528).

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

81530016 is a wasteful number, since it uses less digits than its factorization.

81530016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 849284 (or 849276 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 81530016 is about 9029.3973220808. The cubic root of 81530016 is about 433.6165428073.

The spelling of 81530016 in words is "eighty-one million, five hundred thirty thousand, sixteen".