81306300 has 36 divisors (see below), whose sum is σ = 235247096. Its totient is φ = 21681600.

The previous prime is 81306299. The next prime is 81306317. The reversal of 81306300 is 360318.

It is a super-2 number, since 2×81306300² = 13221428839380000, which contains 22 as substring.

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 11 ways as a sum of consecutive naturals, for example, 135211 + ... + 135810.

Almost surely, 2^81306300 is an apocalyptic number.

It is an amenable number.

81306300 is an abundant number, since it is smaller than the sum of its proper divisors (153940796).

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

81306300 is a wasteful number, since it uses less digits than its factorization.

81306300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 271038 (or 271031 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 81306300 is about 9017.0006099589. Note that the first 3 decimals coincide. The cubic root of 81306300 is about 433.2195690838.

Adding to 81306300 its reverse (360318), we get a palindrome (81666618).

The spelling of 81306300 in words is "eighty-one million, three hundred six thousand, three hundred".