81617528 has 8 divisors (see below), whose sum is σ = 153032880. Its totient is φ = 40808760.

The previous prime is 81617519. The next prime is 81617531. The reversal of 81617528 is 82571618.

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

It is a super-2 number, since 2×81617528² = 13322841753661568, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81617491 and 81617500.

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, 5101088 + ... + 5101103.

It is an arithmetic number, because the mean of its divisors is an integer number (19129110).

Almost surely, 2^81617528 is an apocalyptic number.

It is an amenable number.

81617528 is a deficient number, since it is larger than the sum of its proper divisors (71415352).

81617528 is a wasteful number, since it uses less digits than its factorization.

81617528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10202197 (or 10202193 counting only the distinct ones).

The product of its digits is 26880, while the sum is 38.

The square root of 81617528 is about 9034.2419715215. The cubic root of 81617528 is about 433.7716312189.

The spelling of 81617528 in words is "eighty-one million, six hundred seventeen thousand, five hundred twenty-eight".