817686145 has 8 divisors (see below), whose sum is σ = 1038942504. Its totient is φ = 615669504.

The previous prime is 817686139. The next prime is 817686161. The reversal of 817686145 is 541686718.

It can be written as a sum of positive squares in 4 ways, for example, as 8340544 + 809345601 = 2888^2 + 28449^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 817686145 - 2⁵ = 817686113 is a prime.

It is a super-2 number, since 2×817686145² = 1337221263449922050, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 817686095 and 817686104.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4809834 + ... + 4810003.

It is an arithmetic number, because the mean of its divisors is an integer number (129867813).

Almost surely, 2^817686145 is an apocalyptic number.

817686145 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

It is an amenable number.

817686145 is a deficient number, since it is larger than the sum of its proper divisors (221256359).

817686145 is a wasteful number, since it uses less digits than its factorization.

817686145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9619859.

The product of its digits is 322560, while the sum is 46.

The square root of 817686145 is about 28595.2119243764. The cubic root of 817686145 is about 935.1089485750.

The spelling of 817686145 in words is "eight hundred seventeen million, six hundred eighty-six thousand, one hundred forty-five".