81000030 has 32 divisors (see below), whose sum is σ = 199656864. Its totient is φ = 21015936.

The previous prime is 81000013. The next prime is 81000037. The reversal of 81000030 is 3000018.

It is a super-2 number, since 2×81000030² = 13122009720001800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81000037) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35377 + ... + 37596.

It is an arithmetic number, because the mean of its divisors is an integer number (6239277).

Almost surely, 2^81000030 is an apocalyptic number.

81000030 is an abundant number, since it is smaller than the sum of its proper divisors (118656834).

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

81000030 is a wasteful number, since it uses less digits than its factorization.

81000030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73020.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 81000030 is about 9000.0016666665. The cubic root of 81000030 is about 432.6749245089.

Subtracting from 81000030 its sum of digits (12), we obtain a palindrome (81000018).

Adding to 81000030 its reverse (3000018), we get a palindrome (84000048).

It can be divided in two parts, 810000 and 30, that multiplied together give a 5-th power (24300000 = 30⁵).

The spelling of 81000030 in words is "eighty-one million, thirty", and thus it is an aban number and an uban number.