689535731 has 4 divisors (see below), whose sum is σ = 704206752. Its totient is φ = 674864712.

The previous prime is 689535709. The next prime is 689535757. The reversal of 689535731 is 137535986.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-689535731 is a prime.

It is a super-2 number, since 2×689535731² = 950919048651408722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (47), and also a Moran number because the ratio is a prime number: 14670973 = 689535731 / (6 + 8 + 9 + 5 + 3 + 5 + 7 + 3 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (689535131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7335440 + ... + 7335533.

It is an arithmetic number, because the mean of its divisors is an integer number (176051688).

Almost surely, 2^689535731 is an apocalyptic number.

689535731 is a deficient number, since it is larger than the sum of its proper divisors (14671021).

689535731 is a wasteful number, since it uses less digits than its factorization.

689535731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14671020.

The product of its digits is 680400, while the sum is 47.

The square root of 689535731 is about 26259.0123767060. The cubic root of 689535731 is about 883.4573574838.

The spelling of 689535731 in words is "six hundred eighty-nine million, five hundred thirty-five thousand, seven hundred thirty-one".