81771484 has 6 divisors (see below), whose sum is σ = 143100104. Its totient is φ = 40885740.

The previous prime is 81771451. The next prime is 81771491. The reversal of 81771484 is 48417718.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10221432 + ... + 10221439.

Almost surely, 2^81771484 is an apocalyptic number.

It is an amenable number.

81771484 is a deficient number, since it is larger than the sum of its proper divisors (61328620).

81771484 is a wasteful number, since it uses less digits than its factorization.

81771484 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20442875 (or 20442873 counting only the distinct ones).

The product of its digits is 50176, while the sum is 40.

The square root of 81771484 is about 9042.7586498811. The cubic root of 81771484 is about 434.0442025667.

The spelling of 81771484 in words is "eighty-one million, seven hundred seventy-one thousand, four hundred eighty-four".