1685385601 has 4 divisors (see below), whose sum is σ = 1701748672. Its totient is φ = 1669022532.

The previous prime is 1685385599. The next prime is 1685385619. The reversal of 1685385601 is 1065835861.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1065835861 = 2551 ⋅417811.

It is a cyclic number.

It is not a de Polignac number, because 1685385601 - 2¹ = 1685385599 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1685385701) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8181381 + ... + 8181586.

It is an arithmetic number, because the mean of its divisors is an integer number (425437168).

Almost surely, 2^1685385601 is an apocalyptic number.

It is an amenable number.

1685385601 is a deficient number, since it is larger than the sum of its proper divisors (16363071).

1685385601 is a wasteful number, since it uses less digits than its factorization.

1685385601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16363070.

The product of its (nonzero) digits is 172800, while the sum is 43.

The square root of 1685385601 is about 41053.4481012253. The cubic root of 1685385601 is about 1190.0533368274.

The spelling of 1685385601 in words is "one billion, six hundred eighty-five million, three hundred eighty-five thousand, six hundred one".