690857 has 4 divisors (see below), whose sum is σ = 692676. Its totient is φ = 689040.

The previous prime is 690841. The next prime is 690869. The reversal of 690857 is 758096.

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

It can be written as a sum of positive squares in 2 ways, for example, as 364816 + 326041 = 604^2 + 571^2 .

It is a cyclic number.

It is not a de Polignac number, because 690857 - 2⁴ = 690841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (690817) 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, 98 + ... + 1179.

It is an arithmetic number, because the mean of its divisors is an integer number (173169).

2⁶⁹⁰⁸⁵⁷ is an apocalyptic number.

It is an amenable number.

690857 is a deficient number, since it is larger than the sum of its proper divisors (1819).

690857 is a wasteful number, since it uses less digits than its factorization.

690857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1818.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 690857 is about 831.1780795955. The cubic root of 690857 is about 88.4021282836.

The spelling of 690857 in words is "six hundred ninety thousand, eight hundred fifty-seven".