638893 has 2 divisors, whose sum is σ = 638894. Its totient is φ = 638892.

The previous prime is 638861. The next prime is 638923. The reversal of 638893 is 398836.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 544644 + 94249 = 738^2 + 307^2 .

It is a cyclic number.

It is not a de Polignac number, because 638893 - 2⁵ = 638861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (638993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319446 + 319447.

It is an arithmetic number, because the mean of its divisors is an integer number (319447).

2⁶³⁸⁸⁹³ is an apocalyptic number.

It is an amenable number.

638893 is a deficient number, since it is larger than the sum of its proper divisors (1).

638893 is an equidigital number, since it uses as much as digits as its factorization.

638893 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31104, while the sum is 37.

The square root of 638893 is about 799.3078255591. The cubic root of 638893 is about 86.1276722762.

The spelling of 638893 in words is "six hundred thirty-eight thousand, eight hundred ninety-three".