245209059817 has 4 divisors (see below), whose sum is σ = 245210303376. Its totient is φ = 245207816260.

The previous prime is 245209059811. The next prime is 245209059827. The reversal of 245209059817 is 718950902542.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-245209059817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (245209059811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 253159 + ... + 744652.

It is an arithmetic number, because the mean of its divisors is an integer number (61302575844).

Almost surely, 2^245209059817 is an apocalyptic number.

It is an amenable number.

245209059817 is a deficient number, since it is larger than the sum of its proper divisors (1243559).

245209059817 is an equidigital number, since it uses as much as digits as its factorization.

245209059817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1243558.

The product of its (nonzero) digits is 1814400, while the sum is 52.

The spelling of 245209059817 in words is "two hundred forty-five billion, two hundred nine million, fifty-nine thousand, eight hundred seventeen".