81439076 has 36 divisors (see below), whose sum is σ = 151303152. Its totient is φ = 38332896.

The previous prime is 81439063. The next prime is 81439081. The reversal of 81439076 is 67093418.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 144371 + ... + 144933.

Almost surely, 2^81439076 is an apocalyptic number.

81439076 is a gapful number since it is divisible by the number (86) formed by its first and last digit.

It is an amenable number.

81439076 is a deficient number, since it is larger than the sum of its proper divisors (69864076).

81439076 is a wasteful number, since it uses less digits than its factorization.

81439076 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 668 (or 637 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 38.

The square root of 81439076 is about 9024.3601435226. The cubic root of 81439076 is about 433.4552616789.

The spelling of 81439076 in words is "eighty-one million, four hundred thirty-nine thousand, seventy-six".