685186421 has 4 divisors (see below), whose sum is σ = 695413152. Its totient is φ = 674959692.

The previous prime is 685186409. The next prime is 685186429. The reversal of 685186421 is 124681586.

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.

It is a cyclic number.

It is not a de Polignac number, because 685186421 - 2⁶ = 685186357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685186429) 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, 5113265 + ... + 5113398.

It is an arithmetic number, because the mean of its divisors is an integer number (173853288).

Almost surely, 2^685186421 is an apocalyptic number.

It is an amenable number.

685186421 is a deficient number, since it is larger than the sum of its proper divisors (10226731).

685186421 is a wasteful number, since it uses less digits than its factorization.

685186421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10226730.

The product of its digits is 92160, while the sum is 41.

The square root of 685186421 is about 26176.0658044711. The cubic root of 685186421 is about 881.5959421369.

The spelling of 685186421 in words is "six hundred eighty-five million, one hundred eighty-six thousand, four hundred twenty-one".