689881637 has 4 divisors (see below), whose sum is σ = 705925440. Its totient is φ = 673837836.

The previous prime is 689881627. The next prime is 689881679. The reversal of 689881637 is 736188986.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-689881637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (689881627) 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 in 3 ways as a sum of consecutive naturals, for example, 8021837 + ... + 8021922.

It is an arithmetic number, because the mean of its divisors is an integer number (176481360).

Almost surely, 2^689881637 is an apocalyptic number.

It is an amenable number.

689881637 is a deficient number, since it is larger than the sum of its proper divisors (16043803).

689881637 is a wasteful number, since it uses less digits than its factorization.

689881637 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16043802.

The product of its digits is 3483648, while the sum is 56.

The square root of 689881637 is about 26265.5979752984. The cubic root of 689881637 is about 883.6050617534.

The spelling of 689881637 in words is "six hundred eighty-nine million, eight hundred eighty-one thousand, six hundred thirty-seven".