81241236 has 36 divisors (see below), whose sum is σ = 205662912. Its totient is φ = 27040464.

The previous prime is 81241231. The next prime is 81241241. The reversal of 81241236 is 63214218.

It is an interprime number because it is at equal distance from previous prime (81241231) and next prime (81241241).

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81241231) by changing a digit.

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, 32901 + ... + 35283.

Almost surely, 2^81241236 is an apocalyptic number.

It is an amenable number.

81241236 is an abundant number, since it is smaller than the sum of its proper divisors (124421676).

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

81241236 is a wasteful number, since it uses less digits than its factorization.

81241236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3340 (or 3335 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 81241236 is about 9013.3920362980. The cubic root of 81241236 is about 433.1039793525.

The spelling of 81241236 in words is "eighty-one million, two hundred forty-one thousand, two hundred thirty-six".