688145957 has 2 divisors, whose sum is σ = 688145958. Its totient is φ = 688145956.

The previous prime is 688145951. The next prime is 688145999. The reversal of 688145957 is 759541886.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 683613316 + 4532641 = 26146^2 + 2129^2 .

It is a cyclic number.

It is not a de Polignac number, because 688145957 - 2⁶ = 688145893 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 688145899 and 688145908.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (688145951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344072978 + 344072979.

It is an arithmetic number, because the mean of its divisors is an integer number (344072979).

Almost surely, 2^688145957 is an apocalyptic number.

It is an amenable number.

688145957 is a deficient number, since it is larger than the sum of its proper divisors (1).

688145957 is an equidigital number, since it uses as much as digits as its factorization.

688145957 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2419200, while the sum is 53.

The square root of 688145957 is about 26232.5362288895. The cubic root of 688145957 is about 882.8634158769.

The spelling of 688145957 in words is "six hundred eighty-eight million, one hundred forty-five thousand, nine hundred fifty-seven".