245679509 has 2 divisors, whose sum is σ = 245679510. Its totient is φ = 245679508.

The previous prime is 245679457. The next prime is 245679517. The reversal of 245679509 is 905976542.

245679509 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 240157009 + 5522500 = 15497^2 + 2350^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-245679509 is a prime.

It is a super-2 number, since 2×245679509² = 120716842284962162, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (245679209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 122839754 + 122839755.

It is an arithmetic number, because the mean of its divisors is an integer number (122839755).

Almost surely, 2^245679509 is an apocalyptic number.

It is an amenable number.

245679509 is a deficient number, since it is larger than the sum of its proper divisors (1).

245679509 is an equidigital number, since it uses as much as digits as its factorization.

245679509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 680400, while the sum is 47.

The square root of 245679509 is about 15674.1669316108. The cubic root of 245679509 is about 626.3104315238.

The spelling of 245679509 in words is "two hundred forty-five million, six hundred seventy-nine thousand, five hundred nine".