81023181 has 16 divisors (see below), whose sum is σ = 116367360. Its totient is φ = 49998960.

The previous prime is 81023171. The next prime is 81023191. The reversal of 81023181 is 18132018.

It is an interprime number because it is at equal distance from previous prime (81023171) and next prime (81023191).

It is not a de Polignac number, because 81023181 - 2⁵ = 81023149 is a prime.

It is a super-2 number, since 2×81023181² = 13129511718717522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81023171) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16801 + ... + 21078.

It is an arithmetic number, because the mean of its divisors is an integer number (7272960).

Almost surely, 2^81023181 is an apocalyptic number.

It is an amenable number.

81023181 is a deficient number, since it is larger than the sum of its proper divisors (35344179).

81023181 is a wasteful number, since it uses less digits than its factorization.

81023181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37936.

The product of its (nonzero) digits is 384, while the sum is 24.

The square root of 81023181 is about 9001.2877412068. The cubic root of 81023181 is about 432.7161422014.

Adding to 81023181 its reverse (18132018), we get a palindrome (99155199).

The spelling of 81023181 in words is "eighty-one million, twenty-three thousand, one hundred eighty-one".