81410531 has 2 divisors, whose sum is σ = 81410532. Its totient is φ = 81410530.

The previous prime is 81410521. The next prime is 81410587. The reversal of 81410531 is 13501418.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81410531 is a prime.

It is a super-2 number, since 2×81410531² = 13255349115403922, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 81410497 and 81410506.

It is not a weakly prime, because it can be changed into another prime (81410521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40705265 + 40705266.

It is an arithmetic number, because the mean of its divisors is an integer number (40705266).

Almost surely, 2^81410531 is an apocalyptic number.

81410531 is a deficient number, since it is larger than the sum of its proper divisors (1).

81410531 is an equidigital number, since it uses as much as digits as its factorization.

81410531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 81410531 is about 9022.7784523394. The cubic root of 81410531 is about 433.4046126664.

Adding to 81410531 its reverse (13501418), we get a palindrome (94911949).

The spelling of 81410531 in words is "eighty-one million, four hundred ten thousand, five hundred thirty-one".