639299 has 2 divisors, whose sum is σ = 639300. Its totient is φ = 639298.

The previous prime is 639269. The next prime is 639307. The reversal of 639299 is 992936.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 639299 - 2⁸ = 639043 is a prime.

It is a super-2 number, since 2×639299² = 817406422802, which contains 22 as substring.

It is a Chen prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (639259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319649 + 319650.

It is an arithmetic number, because the mean of its divisors is an integer number (319650).

2⁶³⁹²⁹⁹ is an apocalyptic number.

639299 is a deficient number, since it is larger than the sum of its proper divisors (1).

639299 is an equidigital number, since it uses as much as digits as its factorization.

639299 is an evil number, because the sum of its binary digits is even.

The product of its digits is 26244, while the sum is 38.

The square root of 639299 is about 799.5617549633. The cubic root of 639299 is about 86.1459123835.

The spelling of 639299 in words is "six hundred thirty-nine thousand, two hundred ninety-nine".