685401636501 has 12 divisors (see below), whose sum is σ = 990043900300. Its totient is φ = 456925510080.

The previous prime is 685401636499. The next prime is 685401636523. The reversal of 685401636501 is 105636104586.

685401636501 is a `hidden beast` number, since 6 + 8 + 5 + 4 + 0 + 1 + 636 + 5 + 0 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 300933433476 + 384468203025 = 548574^2 + 620055^2 .

It is not a de Polignac number, because 685401636501 - 2¹ = 685401636499 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685401636551) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 237826 + ... + 1194723.

Almost surely, 2^685401636501 is an apocalyptic number.

It is an amenable number.

685401636501 is a deficient number, since it is larger than the sum of its proper divisors (304642263799).

685401636501 is a wasteful number, since it uses less digits than its factorization.

685401636501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1485716 (or 1485713 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The spelling of 685401636501 in words is "six hundred eighty-five billion, four hundred one million, six hundred thirty-six thousand, five hundred one".