625638239 has 2 divisors, whose sum is σ = 625638240. Its totient is φ = 625638238.

The previous prime is 625638193. The next prime is 625638241. The reversal of 625638239 is 932836526.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-625638239 is a prime.

It is a super-2 number, since 2×625638239² = 782846412198042242, which contains 22 as substring.

Together with 625638241, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 625638239.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (625638259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312819119 + 312819120.

It is an arithmetic number, because the mean of its divisors is an integer number (312819120).

Almost surely, 2^625638239 is an apocalyptic number.

625638239 is a deficient number, since it is larger than the sum of its proper divisors (1).

625638239 is an equidigital number, since it uses as much as digits as its factorization.

625638239 is an evil number, because the sum of its binary digits is even.

The product of its digits is 466560, while the sum is 44.

The square root of 625638239 is about 25012.7615228707. The cubic root of 625638239 is about 855.2789072188.

The spelling of 625638239 in words is "six hundred twenty-five million, six hundred thirty-eight thousand, two hundred thirty-nine".