688890137 has 12 divisors (see below), whose sum is σ = 752821740. Its totient is φ = 630047808.

The previous prime is 688890127. The next prime is 688890179. The reversal of 688890137 is 731098886.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 106584976 + 582305161 = 10324^2 + 24131^2 .

It is not a de Polignac number, because 688890137 - 2¹⁴ = 688873753 is a prime.

It is a super-3 number, since 3×688890137³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (688890107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 278 + ... + 37119.

It is an arithmetic number, because the mean of its divisors is an integer number (62735145).

Almost surely, 2^688890137 is an apocalyptic number.

It is an amenable number.

688890137 is a deficient number, since it is larger than the sum of its proper divisors (63931603).

688890137 is a wasteful number, since it uses less digits than its factorization.

688890137 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37532 (or 37519 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 50.

The square root of 688890137 is about 26246.7166899024. The cubic root of 688890137 is about 883.1815521658.

The spelling of 688890137 in words is "six hundred eighty-eight million, eight hundred ninety thousand, one hundred thirty-seven".