245685221 has 2 divisors, whose sum is σ = 245685222. Its totient is φ = 245685220.

The previous prime is 245685211. The next prime is 245685233. The reversal of 245685221 is 122586542.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 230584225 + 15100996 = 15185^2 + 3886^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-245685221 is a prime.

It is a super-2 number, since 2×245685221² = 120722455635637682, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (245685211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 122842610 + 122842611.

It is an arithmetic number, because the mean of its divisors is an integer number (122842611).

Almost surely, 2^245685221 is an apocalyptic number.

It is an amenable number.

245685221 is a deficient number, since it is larger than the sum of its proper divisors (1).

245685221 is an equidigital number, since it uses as much as digits as its factorization.

245685221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38400, while the sum is 35.

The square root of 245685221 is about 15674.3491411924. The cubic root of 245685221 is about 626.3152853508.

The spelling of 245685221 in words is "two hundred forty-five million, six hundred eighty-five thousand, two hundred twenty-one".