625684621 has 2 divisors, whose sum is σ = 625684622. Its totient is φ = 625684620.

The previous prime is 625684603. The next prime is 625684637. The reversal of 625684621 is 126486526.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 585107721 + 40576900 = 24189^2 + 6370^2 .

It is a cyclic number.

It is not a de Polignac number, because 625684621 - 2¹⁵ = 625651853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (625684651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312842310 + 312842311.

It is an arithmetic number, because the mean of its divisors is an integer number (312842311).

Almost surely, 2^625684621 is an apocalyptic number.

It is an amenable number.

625684621 is a deficient number, since it is larger than the sum of its proper divisors (1).

625684621 is an equidigital number, since it uses as much as digits as its factorization.

625684621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 138240, while the sum is 40.

The square root of 625684621 is about 25013.6886724050. The cubic root of 625684621 is about 855.3000422047.

The spelling of 625684621 in words is "six hundred twenty-five million, six hundred eighty-four thousand, six hundred twenty-one".