81352340 has 12 divisors (see below), whose sum is σ = 170839956. Its totient is φ = 32540928.

The previous prime is 81352331. The next prime is 81352351. The reversal of 81352340 is 4325318.

It can be written as a sum of positive squares in 2 ways, for example, as 11930116 + 69422224 = 3454^2 + 8332^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2033789 + ... + 2033828.

It is an arithmetic number, because the mean of its divisors is an integer number (14236663).

Almost surely, 2^81352340 is an apocalyptic number.

It is an amenable number.

81352340 is an abundant number, since it is smaller than the sum of its proper divisors (89487616).

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

81352340 is a wasteful number, since it uses less digits than its factorization.

81352340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4067626 (or 4067624 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 81352340 is about 9019.5532040118. The cubic root of 81352340 is about 433.3013243944.

Adding to 81352340 its reverse (4325318), we get a palindrome (85677658).

The spelling of 81352340 in words is "eighty-one million, three hundred fifty-two thousand, three hundred forty".