81894892 has 6 divisors (see below), whose sum is σ = 143316068. Its totient is φ = 40947444.

The previous prime is 81894889. The next prime is 81894893. The reversal of 81894892 is 29849818.

It is not an unprimeable number, because it can be changed into a prime (81894893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10236858 + ... + 10236865.

Almost surely, 2^81894892 is an apocalyptic number.

It is an amenable number.

81894892 is a deficient number, since it is larger than the sum of its proper divisors (61421176).

81894892 is a wasteful number, since it uses less digits than its factorization.

81894892 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20473727 (or 20473725 counting only the distinct ones).

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

The square root of 81894892 is about 9049.5796587466. The cubic root of 81894892 is about 434.2624432896.

The spelling of 81894892 in words is "eighty-one million, eight hundred ninety-four thousand, eight hundred ninety-two".