688145999 has 2 divisors, whose sum is σ = 688146000. Its totient is φ = 688145998.

The previous prime is 688145957. The next prime is 688146007. The reversal of 688145999 is 999541886.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-688145999 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (688115999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344072999 + 344073000.

It is an arithmetic number, because the mean of its divisors is an integer number (344073000).

Almost surely, 2^688145999 is an apocalyptic number.

688145999 is a deficient number, since it is larger than the sum of its proper divisors (1).

688145999 is an equidigital number, since it uses as much as digits as its factorization.

688145999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5598720, while the sum is 59.

The square root of 688145999 is about 26232.5370294221. The cubic root of 688145999 is about 882.8634338383.

The spelling of 688145999 in words is "six hundred eighty-eight million, one hundred forty-five thousand, nine hundred ninety-nine".