638633 has 2 divisors, whose sum is σ = 638634. Its totient is φ = 638632.

The previous prime is 638629. The next prime is 638663. The reversal of 638633 is 336836.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 620944 + 17689 = 788^2 + 133^2 .

It is a cyclic number.

It is not a de Polignac number, because 638633 - 2² = 638629 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 638596 and 638605.

It is not a weakly prime, because it can be changed into another prime (638663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319316 + 319317.

It is an arithmetic number, because the mean of its divisors is an integer number (319317).

2⁶³⁸⁶³³ is an apocalyptic number.

It is an amenable number.

638633 is a deficient number, since it is larger than the sum of its proper divisors (1).

638633 is an equidigital number, since it uses as much as digits as its factorization.

638633 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7776, while the sum is 29.

The square root of 638633 is about 799.1451682892. The cubic root of 638633 is about 86.1159873602.

The spelling of 638633 in words is "six hundred thirty-eight thousand, six hundred thirty-three".