81981748 has 12 divisors (see below), whose sum is σ = 143540320. Its totient is φ = 40970232.

The previous prime is 81981719. The next prime is 81981761. The reversal of 81981748 is 84718918.

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 81981698 and 81981707.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6913 + ... + 14551.

Almost surely, 2^81981748 is an apocalyptic number.

It is an amenable number.

81981748 is a deficient number, since it is larger than the sum of its proper divisors (61558572).

81981748 is a wasteful number, since it uses less digits than its factorization.

81981748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10326 (or 10324 counting only the distinct ones).

The product of its digits is 129024, while the sum is 46.

The square root of 81981748 is about 9054.3772839439. The cubic root of 81981748 is about 434.4159122516.

The spelling of 81981748 in words is "eighty-one million, nine hundred eighty-one thousand, seven hundred forty-eight".