81854772 has 12 divisors (see below), whose sum is σ = 190994496. Its totient is φ = 27284920.

The previous prime is 81854761. The next prime is 81854783. The reversal of 81854772 is 27745818.

It is an interprime number because it is at equal distance from previous prime (81854761) and next prime (81854783).

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3410604 + ... + 3410627.

It is an arithmetic number, because the mean of its divisors is an integer number (15916208).

Almost surely, 2^81854772 is an apocalyptic number.

It is an amenable number.

81854772 is an abundant number, since it is smaller than the sum of its proper divisors (109139724).

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

81854772 is a wasteful number, since it uses less digits than its factorization.

81854772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6821238 (or 6821236 counting only the distinct ones).

The product of its digits is 125440, while the sum is 42.

The square root of 81854772 is about 9047.3627096519. The cubic root of 81854772 is about 434.1915171929.

The spelling of 81854772 in words is "eighty-one million, eight hundred fifty-four thousand, seven hundred seventy-two".