625797209 has 2 divisors, whose sum is σ = 625797210. Its totient is φ = 625797208.

The previous prime is 625797197. The next prime is 625797253. The reversal of 625797209 is 902797526.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 613651984 + 12145225 = 24772^2 + 3485^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-625797209 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (625797269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312898604 + 312898605.

It is an arithmetic number, because the mean of its divisors is an integer number (312898605).

Almost surely, 2^625797209 is an apocalyptic number.

It is an amenable number.

625797209 is a deficient number, since it is larger than the sum of its proper divisors (1).

625797209 is an equidigital number, since it uses as much as digits as its factorization.

625797209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 476280, while the sum is 47.

The square root of 625797209 is about 25015.9390989025. The cubic root of 625797209 is about 855.3513410766.

The spelling of 625797209 in words is "six hundred twenty-five million, seven hundred ninety-seven thousand, two hundred nine".