81355452 has 48 divisors (see below), whose sum is σ = 197074080. Its totient is φ = 26099712.

The previous prime is 81355381. The next prime is 81355453. The reversal of 81355452 is 25455318.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81355453) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42124 + ... + 44012.

It is an arithmetic number, because the mean of its divisors is an integer number (4105710).

Almost surely, 2^81355452 is an apocalyptic number.

It is an amenable number.

81355452 is an abundant number, since it is smaller than the sum of its proper divisors (115718628).

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

81355452 is a wasteful number, since it uses less digits than its factorization.

81355452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2030 (or 2028 counting only the distinct ones).

The product of its digits is 24000, while the sum is 33.

The square root of 81355452 is about 9019.7257164506. The cubic root of 81355452 is about 433.3068494005.

It can be divided in two parts, 813 and 55452, that added together give a palindrome (56265).

The spelling of 81355452 in words is "eighty-one million, three hundred fifty-five thousand, four hundred fifty-two".