245693681 has 2 divisors, whose sum is σ = 245693682. Its totient is φ = 245693680.

The previous prime is 245693671. The next prime is 245693717. The reversal of 245693681 is 186396542.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 245079025 + 614656 = 15655^2 + 784^2 .

It is a cyclic number.

It is not a de Polignac number, because 245693681 - 2²⁶ = 178584817 is a prime.

It is a super-2 number, since 2×245693681² = 120730769766659522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (245693621) 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, 122846840 + 122846841.

It is an arithmetic number, because the mean of its divisors is an integer number (122846841).

Almost surely, 2^245693681 is an apocalyptic number.

It is an amenable number.

245693681 is a deficient number, since it is larger than the sum of its proper divisors (1).

245693681 is an equidigital number, since it uses as much as digits as its factorization.

245693681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 311040, while the sum is 44.

The square root of 245693681 is about 15674.6190065341. The cubic root of 245693681 is about 626.3224741789.

The spelling of 245693681 in words is "two hundred forty-five million, six hundred ninety-three thousand, six hundred eighty-one".