81203365 has 8 divisors (see below), whose sum is σ = 98338680. Its totient is φ = 64366272.

The previous prime is 81203351. The next prime is 81203371. The reversal of 81203365 is 56330218.

It can be written as a sum of positive squares in 4 ways, for example, as 42850116 + 38353249 = 6546^2 + 6193^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81203365 - 2⁹ = 81202853 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 73954 + ... + 75043.

It is an arithmetic number, because the mean of its divisors is an integer number (12292335).

Almost surely, 2^81203365 is an apocalyptic number.

It is an amenable number.

81203365 is a deficient number, since it is larger than the sum of its proper divisors (17135315).

81203365 is a wasteful number, since it uses less digits than its factorization.

81203365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149111.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 81203365 is about 9011.2909729960. The cubic root of 81203365 is about 433.0366710458.

The spelling of 81203365 in words is "eighty-one million, two hundred three thousand, three hundred sixty-five".