688863971 has 2 divisors, whose sum is σ = 688863972. Its totient is φ = 688863970.

The previous prime is 688863863. The next prime is 688863983. The reversal of 688863971 is 179368886.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 688863971 - 2¹⁰ = 688862947 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (688863991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344431985 + 344431986.

It is an arithmetic number, because the mean of its divisors is an integer number (344431986).

Almost surely, 2^688863971 is an apocalyptic number.

688863971 is a deficient number, since it is larger than the sum of its proper divisors (1).

688863971 is an equidigital number, since it uses as much as digits as its factorization.

688863971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3483648, while the sum is 56.

The square root of 688863971 is about 26246.2182228221. The cubic root of 688863971 is about 883.1703701114.

The spelling of 688863971 in words is "six hundred eighty-eight million, eight hundred sixty-three thousand, nine hundred seventy-one".