625001621 has 2 divisors, whose sum is σ = 625001622. Its totient is φ = 625001620.

The previous prime is 625001567. The next prime is 625001639. The reversal of 625001621 is 126100526.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 573363025 + 51638596 = 23945^2 + 7186^2 .

It is a cyclic number.

It is not a de Polignac number, because 625001621 - 2⁶ = 625001557 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (625004621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312500810 + 312500811.

It is an arithmetic number, because the mean of its divisors is an integer number (312500811).

Almost surely, 2^625001621 is an apocalyptic number.

It is an amenable number.

625001621 is a deficient number, since it is larger than the sum of its proper divisors (1).

625001621 is an equidigital number, since it uses as much as digits as its factorization.

625001621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 625001621 is about 25000.0324199790. The cubic root of 625001621 is about 854.9887125033.

The spelling of 625001621 in words is "six hundred twenty-five million, one thousand, six hundred twenty-one".