689223749 has 2 divisors, whose sum is σ = 689223750. Its totient is φ = 689223748.

The previous prime is 689223709. The next prime is 689223761. The reversal of 689223749 is 947322986.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 498093124 + 191130625 = 22318^2 + 13825^2 .

It is a cyclic number.

It is not a de Polignac number, because 689223749 - 2¹² = 689219653 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 689223697 and 689223706.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (689223709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344611874 + 344611875.

It is an arithmetic number, because the mean of its divisors is an integer number (344611875).

Almost surely, 2^689223749 is an apocalyptic number.

It is an amenable number.

689223749 is a deficient number, since it is larger than the sum of its proper divisors (1).

689223749 is an equidigital number, since it uses as much as digits as its factorization.

689223749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1306368, while the sum is 50.

The square root of 689223749 is about 26253.0712298580. The cubic root of 689223749 is about 883.3240966243.

The spelling of 689223749 in words is "six hundred eighty-nine million, two hundred twenty-three thousand, seven hundred forty-nine".