81485712 has 120 divisors (see below), whose sum is σ = 284356800. Its totient is φ = 21162240.

The previous prime is 81485687. The next prime is 81485713. The reversal of 81485712 is 21758418.

81485712 is a `hidden beast` number, since 81 + 4 + 8 + 571 + 2 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (81485713) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7414 + ... + 14762.

It is an arithmetic number, because the mean of its divisors is an integer number (2369640).

Almost surely, 2^81485712 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81485712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142178400).

81485712 is an abundant number, since it is smaller than the sum of its proper divisors (202871088).

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

81485712 is a wasteful number, since it uses less digits than its factorization.

81485712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7381 (or 7372 counting only the distinct ones).

The product of its digits is 17920, while the sum is 36.

The square root of 81485712 is about 9026.9436688173. The cubic root of 81485712 is about 433.5379851215.

The spelling of 81485712 in words is "eighty-one million, four hundred eighty-five thousand, seven hundred twelve".