1685370653 has 4 divisors (see below), whose sum is σ = 1685453340. Its totient is φ = 1685287968.

The previous prime is 1685370649. The next prime is 1685370677. The reversal of 1685370653 is 3560735861.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 3560735861 = 56171 ⋅63391.

It can be written as a sum of positive squares in 2 ways, for example, as 1556933764 + 128436889 = 39458^2 + 11333^2 .

It is a cyclic number.

It is not a de Polignac number, because 1685370653 - 2² = 1685370649 is a prime.

It is a Duffinian number.

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1685379653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13343 + ... + 59571.

It is an arithmetic number, because the mean of its divisors is an integer number (421363335).

Almost surely, 2^1685370653 is an apocalyptic number.

It is an amenable number.

1685370653 is a deficient number, since it is larger than the sum of its proper divisors (82687).

1685370653 is an equidigital number, since it uses as much as digits as its factorization.

1685370653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82686.

The product of its (nonzero) digits is 453600, while the sum is 44.

The square root of 1685370653 is about 41053.2660454683. The cubic root of 1685370653 is about 1190.0498185485.

The spelling of 1685370653 in words is "one billion, six hundred eighty-five million, three hundred seventy thousand, six hundred fifty-three".