81033531 has 8 divisors (see below), whose sum is σ = 112742400. Its totient is φ = 51673512.

The previous prime is 81033529. The next prime is 81033541. The reversal of 81033531 is 13533018.

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

It is not a de Polignac number, because 81033531 - 2¹ = 81033529 is a prime.

It is a super-2 number, since 2×81033531² = 13132866292655922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81033541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 587131 + ... + 587268.

It is an arithmetic number, because the mean of its divisors is an integer number (14092800).

Almost surely, 2^81033531 is an apocalyptic number.

81033531 is a deficient number, since it is larger than the sum of its proper divisors (31708869).

81033531 is a wasteful number, since it uses less digits than its factorization.

81033531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1174425.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 81033531 is about 9001.8626405872. The cubic root of 81033531 is about 432.7345666463.

Adding to 81033531 its reverse (13533018), we get a palindrome (94566549).

The spelling of 81033531 in words is "eighty-one million, thirty-three thousand, five hundred thirty-one".