689685533 has 2 divisors, whose sum is σ = 689685534. Its totient is φ = 689685532.

The previous prime is 689685527. The next prime is 689685539. The reversal of 689685533 is 335586986.

It is a balanced prime because it is at equal distance from previous prime (689685527) and next prime (689685539).

It can be written as a sum of positive squares in only one way, i.e., 492928804 + 196756729 = 22202^2 + 14027^2 .

It is a cyclic number.

It is not a de Polignac number, because 689685533 - 2⁴ = 689685517 is a prime.

It is a super-2 number, since 2×689685533² = 951332268858988178, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (689685539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344842766 + 344842767.

It is an arithmetic number, because the mean of its divisors is an integer number (344842767).

Almost surely, 2^689685533 is an apocalyptic number.

It is an amenable number.

689685533 is a deficient number, since it is larger than the sum of its proper divisors (1).

689685533 is an equidigital number, since it uses as much as digits as its factorization.

689685533 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4665600, while the sum is 53.

The square root of 689685533 is about 26261.8646139226. The cubic root of 689685533 is about 883.5213300431.

It can be divided in two parts, 6896 and 85533, that added together give a palindrome (92429).

The spelling of 689685533 in words is "six hundred eighty-nine million, six hundred eighty-five thousand, five hundred thirty-three".