81717448 has 8 divisors (see below), whose sum is σ = 153220230. Its totient is φ = 40858720.

The previous prime is 81717437. The next prime is 81717451. The reversal of 81717448 is 84471718.

It can be written as a sum of positive squares in only one way, i.e., 75377124 + 6340324 = 8682^2 + 2518^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 81717448.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5107333 + ... + 5107348.

Almost surely, 2^81717448 is an apocalyptic number.

It is an amenable number.

81717448 is a deficient number, since it is larger than the sum of its proper divisors (71502782).

81717448 is a wasteful number, since it uses less digits than its factorization.

81717448 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10214687 (or 10214683 counting only the distinct ones).

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

The square root of 81717448 is about 9039.7703510653. The cubic root of 81717448 is about 433.9485735465.

The spelling of 81717448 in words is "eighty-one million, seven hundred seventeen thousand, four hundred forty-eight".