81408104 has 32 divisors (see below), whose sum is σ = 167200200. Its totient is φ = 36986880.

The previous prime is 81408101. The next prime is 81408161. The reversal of 81408104 is 40180418.

It can be written as a sum of positive squares in 4 ways, for example, as 67732900 + 13675204 = 8230^2 + 3698^2 .

It is not an unprimeable number, because it can be changed into a prime (81408101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6377 + ... + 14264.

Almost surely, 2^81408104 is an apocalyptic number.

It is an amenable number.

81408104 is an abundant number, since it is smaller than the sum of its proper divisors (85792096).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81408104 is a wasteful number, since it uses less digits than its factorization.

81408104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20693 (or 20689 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 26.

The square root of 81408104 is about 9022.6439583971. The cubic root of 81408104 is about 433.4003057566.

The spelling of 81408104 in words is "eighty-one million, four hundred eight thousand, one hundred four".