81405410 has 32 divisors (see below), whose sum is σ = 150370560. Its totient is φ = 31715712.

The previous prime is 81405409. The next prime is 81405413. The reversal of 81405410 is 1450418.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81405413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 177902 + ... + 178358.

It is an arithmetic number, because the mean of its divisors is an integer number (4699080).

Almost surely, 2^81405410 is an apocalyptic number.

81405410 is a deficient number, since it is larger than the sum of its proper divisors (68965150).

81405410 is a wasteful number, since it uses less digits than its factorization.

81405410 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 890.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 81405410 is about 9022.4946661109. The cubic root of 81405410 is about 433.3955249332.

Adding to 81405410 its reverse (1450418), we get a palindrome (82855828).

The spelling of 81405410 in words is "eighty-one million, four hundred five thousand, four hundred ten".