639253 has 2 divisors, whose sum is σ = 639254. Its totient is φ = 639252.

The previous prime is 639211. The next prime is 639257. The reversal of 639253 is 352936.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 628849 + 10404 = 793^2 + 102^2 .

It is a cyclic number.

It is not a de Polignac number, because 639253 - 2¹³ = 631061 is a prime.

639253 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (639257) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319626 + 319627.

It is an arithmetic number, because the mean of its divisors is an integer number (319627).

2⁶³⁹²⁵³ is an apocalyptic number.

It is an amenable number.

639253 is a deficient number, since it is larger than the sum of its proper divisors (1).

639253 is an equidigital number, since it uses as much as digits as its factorization.

639253 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4860, while the sum is 28.

The square root of 639253 is about 799.5329886878. The cubic root of 639253 is about 86.1438461583.

It can be divided in two parts, 63 and 9253, that added together give a triangular number (9316 = T₁₃₆).

The spelling of 639253 in words is "six hundred thirty-nine thousand, two hundred fifty-three".