625997521 has 2 divisors, whose sum is σ = 625997522. Its totient is φ = 625997520.

The previous prime is 625997507. The next prime is 625997527. The reversal of 625997521 is 125799526.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 470022400 + 155975121 = 21680^2 + 12489^2 .

It is a cyclic number.

It is not a de Polignac number, because 625997521 - 2²³ = 617608913 is a prime.

It is not a weakly prime, because it can be changed into another prime (625997527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312998760 + 312998761.

It is an arithmetic number, because the mean of its divisors is an integer number (312998761).

Almost surely, 2^625997521 is an apocalyptic number.

It is an amenable number.

625997521 is a deficient number, since it is larger than the sum of its proper divisors (1).

625997521 is an equidigital number, since it uses as much as digits as its factorization.

625997521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 340200, while the sum is 46.

The square root of 625997521 is about 25019.9424659610. The cubic root of 625997521 is about 855.4425947381.

The spelling of 625997521 in words is "six hundred twenty-five million, nine hundred ninety-seven thousand, five hundred twenty-one".