690138 has 24 divisors (see below), whose sum is σ = 1561248. Its totient is φ = 219912.

The previous prime is 690127. The next prime is 690139. The reversal of 690138 is 831096.

It is a Curzon number.

It is a nialpdrome in base 15.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 690138.

It is not an unprimeable number, because it can be changed into a prime (690139) 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 11 ways as a sum of consecutive naturals, for example, 420 + ... + 1247.

It is an arithmetic number, because the mean of its divisors is an integer number (65052).

2⁶⁹⁰¹³⁸ is an apocalyptic number.

690138 is an abundant number, since it is smaller than the sum of its proper divisors (871110).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

690138 is a wasteful number, since it uses less digits than its factorization.

690138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1698 (or 1695 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 690138 is about 830.7454483775. The cubic root of 690138 is about 88.3714498686.

It can be divided in two parts, 690 and 138, that added together give a palindrome (828).

The spelling of 690138 in words is "six hundred ninety thousand, one hundred thirty-eight".