81236534 has 8 divisors (see below), whose sum is σ = 125148288. Its totient is φ = 39520440.

The previous prime is 81236531. The next prime is 81236537. The reversal of 81236534 is 43563218.

It is an interprime number because it is at equal distance from previous prime (81236531) and next prime (81236537).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 81236534.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81236531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 548822 + ... + 548969.

It is an arithmetic number, because the mean of its divisors is an integer number (15643536).

Almost surely, 2^81236534 is an apocalyptic number.

81236534 is a deficient number, since it is larger than the sum of its proper divisors (43911754).

81236534 is a wasteful number, since it uses less digits than its factorization.

81236534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1097830.

The product of its digits is 17280, while the sum is 32.

The square root of 81236534 is about 9013.1311984238. The cubic root of 81236534 is about 433.0956236032.

The spelling of 81236534 in words is "eighty-one million, two hundred thirty-six thousand, five hundred thirty-four".