81236743 has 16 divisors (see below), whose sum is σ = 96768000. Its totient is φ = 66723552.

The previous prime is 81236731. The next prime is 81236747. The reversal of 81236743 is 34763218.

It is a happy number.

It is not a de Polignac number, because 81236743 - 2⁹ = 81236231 is a prime.

It is a super-3 number, since 3×81236743³ (a number of 25 digits) contains 333 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 81236699 and 81236708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81236747) 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, 26778 + ... + 29656.

It is an arithmetic number, because the mean of its divisors is an integer number (6048000).

Almost surely, 2^81236743 is an apocalyptic number.

81236743 is a deficient number, since it is larger than the sum of its proper divisors (15531257).

81236743 is a wasteful number, since it uses less digits than its factorization.

81236743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3054.

The product of its digits is 24192, while the sum is 34.

The square root of 81236743 is about 9013.1427926112. The cubic root of 81236743 is about 433.0959950162.

The spelling of 81236743 in words is "eighty-one million, two hundred thirty-six thousand, seven hundred forty-three".