688242571 has 4 divisors (see below), whose sum is σ = 692363952. Its totient is φ = 684121192.

The previous prime is 688242553. The next prime is 688242617. The reversal of 688242571 is 175242886.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-688242571 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (688242521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2060440 + ... + 2060773.

It is an arithmetic number, because the mean of its divisors is an integer number (173090988).

Almost surely, 2^688242571 is an apocalyptic number.

688242571 is a deficient number, since it is larger than the sum of its proper divisors (4121381).

688242571 is a wasteful number, since it uses less digits than its factorization.

688242571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4121380.

The product of its digits is 215040, while the sum is 43.

The square root of 688242571 is about 26234.3776560451. The cubic root of 688242571 is about 882.9047312275.

The spelling of 688242571 in words is "six hundred eighty-eight million, two hundred forty-two thousand, five hundred seventy-one".