81252031 has 8 divisors (see below), whose sum is σ = 96897024. Its totient is φ = 66616440.

The previous prime is 81252029. The next prime is 81252047. The reversal of 81252031 is 13025218.

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

It is a cyclic number.

It is not a de Polignac number, because 81252031 - 2¹ = 81252029 is a prime.

It is a super-2 number, since 2×81252031² = 13203785083249922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81251993 and 81252011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81252001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252175 + ... + 252496.

It is an arithmetic number, because the mean of its divisors is an integer number (12112128).

Almost surely, 2^81252031 is an apocalyptic number.

81252031 is a deficient number, since it is larger than the sum of its proper divisors (15644993).

81252031 is a wasteful number, since it uses less digits than its factorization.

81252031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504701.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 81252031 is about 9013.9908475658. The cubic root of 81252031 is about 433.1231615258.

Adding to 81252031 its reverse (13025218), we get a palindrome (94277249).

The spelling of 81252031 in words is "eighty-one million, two hundred fifty-two thousand, thirty-one".