686219045 has 4 divisors (see below), whose sum is σ = 823462860. Its totient is φ = 548975232.

The previous prime is 686219033. The next prime is 686219071. The reversal of 686219045 is 540912686.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 540912686 = 2 ⋅270456343.

It can be written as a sum of positive squares in 2 ways, for example, as 86899684 + 599319361 = 9322^2 + 24481^2 .

It is a cyclic number.

It is not a de Polignac number, because 686219045 - 2⁸ = 686218789 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 686218993 and 686219011.

It is a congruent number.

It is an unprimeable number.

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, 68621900 + ... + 68621909.

It is an arithmetic number, because the mean of its divisors is an integer number (205865715).

Almost surely, 2^686219045 is an apocalyptic number.

It is an amenable number.

686219045 is a deficient number, since it is larger than the sum of its proper divisors (137243815).

686219045 is a wasteful number, since it uses less digits than its factorization.

686219045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137243814.

The product of its (nonzero) digits is 103680, while the sum is 41.

The square root of 686219045 is about 26195.7829621487. The cubic root of 686219045 is about 882.0385954834.

The spelling of 686219045 in words is "six hundred eighty-six million, two hundred nineteen thousand, forty-five".