81609301 has 4 divisors (see below), whose sum is σ = 82450732. Its totient is φ = 80767872.

The previous prime is 81609293. The next prime is 81609337. The reversal of 81609301 is 10390618.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 33292900 + 48316401 = 5770^2 + 6951^2 .

It is a cyclic number.

It is not a de Polignac number, because 81609301 - 2³ = 81609293 is a prime.

It is a super-3 number, since 3×81609301³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81609301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81609371) by changing a digit.

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, 420570 + ... + 420763.

It is an arithmetic number, because the mean of its divisors is an integer number (20612683).

Almost surely, 2^81609301 is an apocalyptic number.

It is an amenable number.

81609301 is a deficient number, since it is larger than the sum of its proper divisors (841431).

81609301 is an equidigital number, since it uses as much as digits as its factorization.

81609301 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 841430.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 81609301 is about 9033.7866368428. The cubic root of 81609301 is about 433.7570560853.

Adding to 81609301 its reverse (10390618), we get a palindrome (91999919).

The spelling of 81609301 in words is "eighty-one million, six hundred nine thousand, three hundred one".