638612 has 12 divisors (see below), whose sum is σ = 1203636. Its totient is φ = 294720.

The previous prime is 638587. The next prime is 638621. The reversal of 638612 is 216836.

It can be written as a sum of positive squares in 2 ways, for example, as 329476 + 309136 = 574^2 + 556^2 .

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a congruent number.

It is an unprimeable number.

638612 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 3 ways as a sum of consecutive naturals, for example, 6089 + ... + 6192.

It is an arithmetic number, because the mean of its divisors is an integer number (100303).

2⁶³⁸⁶¹² is an apocalyptic number.

It is an amenable number.

638612 is a deficient number, since it is larger than the sum of its proper divisors (565024).

638612 is a wasteful number, since it uses less digits than its factorization.

638612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12298 (or 12296 counting only the distinct ones).

The product of its digits is 1728, while the sum is 26.

The square root of 638612 is about 799.1320291416. The cubic root of 638612 is about 86.1150434401.

The spelling of 638612 in words is "six hundred thirty-eight thousand, six hundred twelve".