81434111 has 4 divisors (see below), whose sum is σ = 88837224. Its totient is φ = 74031000.

The previous prime is 81434107. The next prime is 81434113. The reversal of 81434111 is 11143418.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81434111 - 2² = 81434107 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 (81434113) 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, 3701540 + ... + 3701561.

It is an arithmetic number, because the mean of its divisors is an integer number (22209306).

Almost surely, 2^81434111 is an apocalyptic number.

81434111 is a deficient number, since it is larger than the sum of its proper divisors (7403113).

81434111 is a wasteful number, since it uses less digits than its factorization.

81434111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7403112.

The product of its digits is 384, while the sum is 23.

The square root of 81434111 is about 9024.0850505744. The cubic root of 81434111 is about 433.4464528482.

Adding to 81434111 its reverse (11143418), we get a palindrome (92577529).

The spelling of 81434111 in words is "eighty-one million, four hundred thirty-four thousand, one hundred eleven".