81632512 has 72 divisors (see below), whose sum is σ = 184859360. Its totient is φ = 35665920.

The previous prime is 81632503. The next prime is 81632527. The reversal of 81632512 is 21523618.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62587 + ... + 63877.

Almost surely, 2^81632512 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 81632512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92429680).

81632512 is an abundant number, since it is smaller than the sum of its proper divisors (103226848).

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

81632512 is a wasteful number, since it uses less digits than its factorization.

81632512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1339 (or 1325 counting only the distinct ones).

The product of its digits is 2880, while the sum is 28.

The square root of 81632512 is about 9035.0712227409. The cubic root of 81632512 is about 433.7981746856.

The spelling of 81632512 in words is "eighty-one million, six hundred thirty-two thousand, five hundred twelve".