626638249 has 2 divisors, whose sum is σ = 626638250. Its totient is φ = 626638248.

The previous prime is 626638237. The next prime is 626638273. The reversal of 626638249 is 942836626.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 623001600 + 3636649 = 24960^2 + 1907^2 .

It is a cyclic number.

It is not a de Polignac number, because 626638249 - 2²³ = 618249641 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 626638199 and 626638208.

It is not a weakly prime, because it can be changed into another prime (626638279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 313319124 + 313319125.

It is an arithmetic number, because the mean of its divisors is an integer number (313319125).

Almost surely, 2^626638249 is an apocalyptic number.

It is an amenable number.

626638249 is a deficient number, since it is larger than the sum of its proper divisors (1).

626638249 is an equidigital number, since it uses as much as digits as its factorization.

626638249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 746496, while the sum is 46.

The square root of 626638249 is about 25032.7435372154. The cubic root of 626638249 is about 855.7343526176.

The spelling of 626638249 in words is "six hundred twenty-six million, six hundred thirty-eight thousand, two hundred forty-nine".