81894928 has 10 divisors (see below), whose sum is σ = 158671454. Its totient is φ = 40947456.

The previous prime is 81894893. The next prime is 81894937. The reversal of 81894928 is 82949818.

It can be written as a sum of positive squares in only one way, i.e., 79423744 + 2471184 = 8912^2 + 1572^2 .

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 2559201 + ... + 2559232.

Almost surely, 2^81894928 is an apocalyptic number.

It is an amenable number.

81894928 is a deficient number, since it is larger than the sum of its proper divisors (76776526).

81894928 is a wasteful number, since it uses less digits than its factorization.

81894928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5118441 (or 5118435 counting only the distinct ones).

The product of its digits is 331776, while the sum is 49.

The square root of 81894928 is about 9049.5816477890. The cubic root of 81894928 is about 434.2625069217.

The spelling of 81894928 in words is "eighty-one million, eight hundred ninety-four thousand, nine hundred twenty-eight".