81512 has 16 divisors (see below), whose sum is σ = 159840. Its totient is φ = 38896.

The previous prime is 81509. The next prime is 81517. The reversal of 81512 is 21518.

It is a super-2 number, since 2×81512² = 13288412288, which contains 22 as substring.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 81512.

It is not an unprimeable number, because it can be changed into a prime (81517) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38 + ... + 405.

It is an arithmetic number, because the mean of its divisors is an integer number (9990).

2⁸¹⁵¹² is an apocalyptic number.

It is an amenable number.

81512 is a deficient number, since it is larger than the sum of its proper divisors (78328).

81512 is a wasteful number, since it uses less digits than its factorization.

81512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 472 (or 468 counting only the distinct ones).

The product of its digits is 80, while the sum is 17.

The square root of 81512 is about 285.5030647821. The cubic root of 81512 is about 43.3584601152.

The spelling of 81512 in words is "eighty-one thousand, five hundred twelve".