689566651 has 2 divisors, whose sum is σ = 689566652. Its totient is φ = 689566650.

The previous prime is 689566649. The next prime is 689566667. The reversal of 689566651 is 156665986.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 689566651 - 2¹ = 689566649 is a prime.

Together with 689566649, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (689566051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344783325 + 344783326.

It is an arithmetic number, because the mean of its divisors is an integer number (344783326).

Almost surely, 2^689566651 is an apocalyptic number.

689566651 is a deficient number, since it is larger than the sum of its proper divisors (1).

689566651 is an equidigital number, since it uses as much as digits as its factorization.

689566651 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2332800, while the sum is 52.

The square root of 689566651 is about 26259.6011203522. The cubic root of 689566651 is about 883.4705625491.

The spelling of 689566651 in words is "six hundred eighty-nine million, five hundred sixty-six thousand, six hundred fifty-one".