81574144 has 72 divisors (see below), whose sum is σ = 177255680. Its totient is φ = 37324800.

The previous prime is 81574127. The next prime is 81574147. The reversal of 81574144 is 44147518.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (81574147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 150514 + ... + 151054.

Almost surely, 2^81574144 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 81574144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88627840).

81574144 is an abundant number, since it is smaller than the sum of its proper divisors (95681536).

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

81574144 is a wasteful number, since it uses less digits than its factorization.

81574144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 607 (or 593 counting only the distinct ones).

The product of its digits is 17920, while the sum is 34.

The square root of 81574144 is about 9031.8405654662. The cubic root of 81574144 is about 433.6947601338.

It can be divided in two parts, 81574 and 144, that added together give a palindrome (81718).

The spelling of 81574144 in words is "eighty-one million, five hundred seventy-four thousand, one hundred forty-four".