689697521645 has 16 divisors (see below), whose sum is σ = 907865038080. Its totient is φ = 498826929600.

The previous prime is 689697521581. The next prime is 689697521647. The reversal of 689697521645 is 546125796986.

It is not a de Polignac number, because 689697521645 - 2⁶ = 689697521581 is a prime.

It is a super-3 number, since 3×689697521645³ (a number of 36 digits) contains 333 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (689697521647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34630805 + ... + 34650714.

It is an arithmetic number, because the mean of its divisors is an integer number (56741564880).

Almost surely, 2^689697521645 is an apocalyptic number.

It is an amenable number.

689697521645 is a deficient number, since it is larger than the sum of its proper divisors (218167516435).

689697521645 is a wasteful number, since it uses less digits than its factorization.

689697521645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69281716.

The product of its digits is 195955200, while the sum is 68.

The spelling of 689697521645 in words is "six hundred eighty-nine billion, six hundred ninety-seven million, five hundred twenty-one thousand, six hundred forty-five".