81020750 has 64 divisors (see below), whose sum is σ = 164324160. Its totient is φ = 29808000.

The previous prime is 81020707. The next prime is 81020777. The reversal of 81020750 is 5702018.

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 31 ways as a sum of consecutive naturals, for example, 175520 + ... + 175980.

It is an arithmetic number, because the mean of its divisors is an integer number (2567565).

Almost surely, 2^81020750 is an apocalyptic number.

81020750 is an abundant number, since it is smaller than the sum of its proper divisors (83303410).

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

81020750 is a wasteful number, since it uses less digits than its factorization.

81020750 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 534 (or 524 counting only the distinct ones).

The product of its (nonzero) digits is 560, while the sum is 23.

The square root of 81020750 is about 9001.1527039596. The cubic root of 81020750 is about 432.7118144545.

Adding to 81020750 its reverse (5702018), we get a palindrome (86722768).

The spelling of 81020750 in words is "eighty-one million, twenty thousand, seven hundred fifty".