688820269 has 2 divisors, whose sum is σ = 688820270. Its totient is φ = 688820268.

The previous prime is 688820239. The next prime is 688820273. The reversal of 688820269 is 962028886.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 399480169 + 289340100 = 19987^2 + 17010^2 .

It is a cyclic number.

It is not a de Polignac number, because 688820269 - 2¹⁵ = 688787501 is a prime.

It is a super-2 number, since 2×688820269² = 948946725970464722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (688820239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344410134 + 344410135.

It is an arithmetic number, because the mean of its divisors is an integer number (344410135).

Almost surely, 2^688820269 is an apocalyptic number.

It is an amenable number.

688820269 is a deficient number, since it is larger than the sum of its proper divisors (1).

688820269 is an equidigital number, since it uses as much as digits as its factorization.

688820269 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 663552, while the sum is 49.

The square root of 688820269 is about 26245.3856706279. The cubic root of 688820269 is about 883.1516934062.

The spelling of 688820269 in words is "six hundred eighty-eight million, eight hundred twenty thousand, two hundred sixty-nine".