81582452 has 72 divisors (see below), whose sum is σ = 177730560. Its totient is φ = 32598720.

The previous prime is 81582433. The next prime is 81582461. The reversal of 81582452 is 25428518.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 175973 + ... + 176435.

It is an arithmetic number, because the mean of its divisors is an integer number (2468480).

Almost surely, 2^81582452 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 81582452, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88865280).

81582452 is an abundant number, since it is smaller than the sum of its proper divisors (96148108).

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

81582452 is a wasteful number, since it uses less digits than its factorization.

81582452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 541 (or 532 counting only the distinct ones).

The product of its digits is 25600, while the sum is 35.

The square root of 81582452 is about 9032.3004821585. The cubic root of 81582452 is about 433.7094829924.

The spelling of 81582452 in words is "eighty-one million, five hundred eighty-two thousand, four hundred fifty-two".