81948992 has 14 divisors (see below), whose sum is σ = 162617658. Its totient is φ = 40974464.

The previous prime is 81948989. The next prime is 81949001. The reversal of 81948992 is 29984918.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 77721856 + 4227136 = 8816^2 + 2056^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 81948992.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 640163 + ... + 640290.

It is an arithmetic number, because the mean of its divisors is an integer number (11615547).

Almost surely, 2^81948992 is an apocalyptic number.

It is an amenable number.

81948992 is a deficient number, since it is larger than the sum of its proper divisors (80668666).

81948992 is a wasteful number, since it uses less digits than its factorization.

81948992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1280465 (or 1280455 counting only the distinct ones).

The product of its digits is 373248, while the sum is 50.

The square root of 81948992 is about 9052.5682543685. The cubic root of 81948992 is about 434.3580472448.

The spelling of 81948992 in words is "eighty-one million, nine hundred forty-eight thousand, nine hundred ninety-two".