245440443509 has 2 divisors, whose sum is σ = 245440443510. Its totient is φ = 245440443508.

The previous prime is 245440443449. The next prime is 245440443511. The reversal of 245440443509 is 905344044542.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 128811363409 + 116629080100 = 358903^2 + 341510^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-245440443509 is a prime.

It is a super-2 number, since 2×245440443509² (a number of 24 digits) contains 22 as substring.

Together with 245440443511, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 245440443509.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (245440443529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 122720221754 + 122720221755.

It is an arithmetic number, because the mean of its divisors is an integer number (122720221755).

Almost surely, 2^245440443509 is an apocalyptic number.

It is an amenable number.

245440443509 is a deficient number, since it is larger than the sum of its proper divisors (1).

245440443509 is an equidigital number, since it uses as much as digits as its factorization.

245440443509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1382400, while the sum is 44.

The spelling of 245440443509 in words is "two hundred forty-five billion, four hundred forty million, four hundred forty-three thousand, five hundred nine".