688161886 has 16 divisors (see below), whose sum is σ = 1078710048. Its totient is φ = 328636000.

The previous prime is 688161869. The next prime is 688161889.

688161886 = 3124² + 3125² + ... + 3192².

688161886 is nontrivially palindromic in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688161889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21576 + ... + 42916.

It is an arithmetic number, because the mean of its divisors is an integer number (67419378).

Almost surely, 2^688161886 is an apocalyptic number.

688161886 is a deficient number, since it is larger than the sum of its proper divisors (390548162).

688161886 is a wasteful number, since it uses less digits than its factorization.

688161886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22067.

The product of its digits is 884736, while the sum is 52.

The square root of 688161886 is about 26232.8398386450. The cubic root of 688161886 is about 882.8702279118.

The spelling of 688161886 in words is "six hundred eighty-eight million, one hundred sixty-one thousand, eight hundred eighty-six".