625540997 has 2 divisors, whose sum is σ = 625540998. Its totient is φ = 625540996.

The previous prime is 625540987. The next prime is 625540999. The reversal of 625540997 is 799045526.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 325766401 + 299774596 = 18049^2 + 17314^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-625540997 is a prime.

Together with 625540999, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (625540999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312770498 + 312770499.

It is an arithmetic number, because the mean of its divisors is an integer number (312770499).

Almost surely, 2^625540997 is an apocalyptic number.

It is an amenable number.

625540997 is a deficient number, since it is larger than the sum of its proper divisors (1).

625540997 is an equidigital number, since it uses as much as digits as its factorization.

625540997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 680400, while the sum is 47.

The square root of 625540997 is about 25010.8175995908. The cubic root of 625540997 is about 855.2345933563.

The spelling of 625540997 in words is "six hundred twenty-five million, five hundred forty thousand, nine hundred ninety-seven".