311638 has 16 divisors (see below), whose sum is σ = 504000. Its totient is φ = 144072.

The previous prime is 311609. The next prime is 311653. The reversal of 311638 is 836113.

It is a congruent number.

It is an unprimeable number.

311638 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2173 + ... + 2311.

It is an arithmetic number, because the mean of its divisors is an integer number (31500).

2³¹¹⁶³⁸ is an apocalyptic number.

311638 is a gapful number since it is divisible by the number (38) formed by its first and last digit.

311638 is a deficient number, since it is larger than the sum of its proper divisors (192362).

311638 is a wasteful number, since it uses less digits than its factorization.

311638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219.

The product of its digits is 432, while the sum is 22.

The square root of 311638 is about 558.2454657227. The cubic root of 311638 is about 67.7979875433.

It can be divided in two parts, 311 and 638, that added together give a palindrome (949).

The spelling of 311638 in words is "three hundred eleven thousand, six hundred thirty-eight".