685724122 has 4 divisors (see below), whose sum is σ = 1028586186. Its totient is φ = 342862060.

The previous prime is 685724107. The next prime is 685724147. The reversal of 685724122 is 221427586.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 555969241 + 129754881 = 23579^2 + 11391^2 .

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 as a sum of consecutive naturals, namely, 171431029 + ... + 171431032.

Almost surely, 2^685724122 is an apocalyptic number.

685724122 is a deficient number, since it is larger than the sum of its proper divisors (342862064).

685724122 is a wasteful number, since it uses less digits than its factorization.

685724122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342862063.

The product of its digits is 53760, while the sum is 37.

The square root of 685724122 is about 26186.3346423282. The cubic root of 685724122 is about 881.8264930543.

The spelling of 685724122 in words is "six hundred eighty-five million, seven hundred twenty-four thousand, one hundred twenty-two".