1685897145 has 20 divisors (see below), whose sum is σ = 3022127460. Its totient is φ = 899144928.

The previous prime is 1685897141. The next prime is 1685897153. The reversal of 1685897145 is 5417985861.

It is a happy number.

1685897145 is a `hidden beast` number, since 16 + 8 + 589 + 7 + 1 + 45 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 273340089 + 1412557056 = 16533^2 + 37584^2 .

It is not a de Polignac number, because 1685897145 - 2² = 1685897141 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1685897091 and 1685897100.

It is not an unprimeable number, because it can be changed into a prime (1685897141) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2080950 + ... + 2081759.

It is an arithmetic number, because the mean of its divisors is an integer number (151106373).

Almost surely, 2^1685897145 is an apocalyptic number.

1685897145 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1685897145 is a deficient number, since it is larger than the sum of its proper divisors (1336230315).

1685897145 is an equidigital number, since it uses as much as digits as its factorization.

1685897145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4162726 (or 4162717 counting only the distinct ones).

The product of its digits is 2419200, while the sum is 54.

The square root of 1685897145 is about 41059.6778482248. The cubic root of 1685897145 is about 1190.1737253138.

It can be divided in two parts, 16858 and 97145, that added together give a triangular number (114003 = T₄₇₇).

The spelling of 1685897145 in words is "one billion, six hundred eighty-five million, eight hundred ninety-seven thousand, one hundred forty-five".