81855068 has 48 divisors (see below), whose sum is σ = 159667200. Its totient is φ = 36520704.

The previous prime is 81855047. The next prime is 81855073. The reversal of 81855068 is 86055818.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 311105 + ... + 311367.

It is an arithmetic number, because the mean of its divisors is an integer number (3326400).

Almost surely, 2^81855068 is an apocalyptic number.

It is an amenable number.

81855068 is a deficient number, since it is larger than the sum of its proper divisors (77812132).

81855068 is a wasteful number, since it uses less digits than its factorization.

81855068 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 506 (or 504 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 41.

The square root of 81855068 is about 9047.3790679953. The cubic root of 81855068 is about 434.1920405610.

The spelling of 81855068 in words is "eighty-one million, eight hundred fifty-five thousand, sixty-eight".