689417221 has 2 divisors, whose sum is σ = 689417222. Its totient is φ = 689417220.

The previous prime is 689417219. The next prime is 689417233. The reversal of 689417221 is 122714986.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 652036225 + 37380996 = 25535^2 + 6114^2 .

It is a cyclic number.

It is not a de Polignac number, because 689417221 - 2¹ = 689417219 is a prime.

It is a super-2 number, since 2×689417221² = 950592209222725682, which contains 22 as substring.

Together with 689417219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (689417251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344708610 + 344708611.

It is an arithmetic number, because the mean of its divisors is an integer number (344708611).

Almost surely, 2^689417221 is an apocalyptic number.

It is an amenable number.

689417221 is a deficient number, since it is larger than the sum of its proper divisors (1).

689417221 is an equidigital number, since it uses as much as digits as its factorization.

689417221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48384, while the sum is 40.

The square root of 689417221 is about 26256.7557211473. The cubic root of 689417221 is about 883.4067415280.

The spelling of 689417221 in words is "six hundred eighty-nine million, four hundred seventeen thousand, two hundred twenty-one".