81412511 has 12 divisors (see below), whose sum is σ = 87873000. Its totient is φ = 75216960.

The previous prime is 81412501. The next prime is 81412517. The reversal of 81412511 is 11521418.

It is a de Polignac number, because none of the positive numbers 2^k-81412511 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81412517) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30665 + ... + 33213.

It is an arithmetic number, because the mean of its divisors is an integer number (7322750).

Almost surely, 2^81412511 is an apocalyptic number.

81412511 is a deficient number, since it is larger than the sum of its proper divisors (6460489).

81412511 is a wasteful number, since it uses less digits than its factorization.

81412511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2650 (or 2609 counting only the distinct ones).

The product of its digits is 320, while the sum is 23.

The square root of 81412511 is about 9022.8881739718. Note that the first 3 decimals coincide. The cubic root of 81412511 is about 433.4081262748.

Adding to 81412511 its reverse (11521418), we get a palindrome (92933929).

The spelling of 81412511 in words is "eighty-one million, four hundred twelve thousand, five hundred eleven".