689215231 has 2 divisors, whose sum is σ = 689215232. Its totient is φ = 689215230.

The previous prime is 689215229. The next prime is 689215273. The reversal of 689215231 is 132512986.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 689215231 - 2¹ = 689215229 is a prime.

It is a super-2 number, since 2×689215231² = 950035269284766722, which contains 22 as substring.

Together with 689215229, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (689215211) 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 as a sum of consecutive naturals, namely, 344607615 + 344607616.

It is an arithmetic number, because the mean of its divisors is an integer number (344607616).

Almost surely, 2^689215231 is an apocalyptic number.

689215231 is a deficient number, since it is larger than the sum of its proper divisors (1).

689215231 is an equidigital number, since it uses as much as digits as its factorization.

689215231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 37.

The square root of 689215231 is about 26252.9090007184. The cubic root of 689215231 is about 883.3204576581.

The spelling of 689215231 in words is "six hundred eighty-nine million, two hundred fifteen thousand, two hundred thirty-one".