690841 has 2 divisors, whose sum is σ = 690842. Its totient is φ = 690840.

The previous prime is 690839. The next prime is 690869. The reversal of 690841 is 148096.

It is an a-pointer prime, because the next prime (690869) can be obtained adding 690841 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 687241 + 3600 = 829^2 + 60^2 .

It is a cyclic number.

It is not a de Polignac number, because 690841 - 2¹ = 690839 is a prime.

It is a super-2 number, since 2×690841² = 954522574562, which contains 22 as substring.

Together with 690839, it forms a pair of twin primes.

It is a Chen prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (690871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345420 + 345421.

It is an arithmetic number, because the mean of its divisors is an integer number (345421).

2⁶⁹⁰⁸⁴¹ is an apocalyptic number.

It is an amenable number.

690841 is a deficient number, since it is larger than the sum of its proper divisors (1).

690841 is an equidigital number, since it uses as much as digits as its factorization.

690841 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 690841 is about 831.1684546468. The cubic root of 690841 is about 88.4014458244.

The spelling of 690841 in words is "six hundred ninety thousand, eight hundred forty-one".