260402509 has 2 divisors, whose sum is σ = 260402510. Its totient is φ = 260402508.

The previous prime is 260402507. The next prime is 260402533. The reversal of 260402509 is 905204062.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 260015625 + 386884 = 16125^2 + 622^2 .

It is a cyclic number.

It is not a de Polignac number, because 260402509 - 2¹ = 260402507 is a prime.

Together with 260402507, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (260402507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130201254 + 130201255.

It is an arithmetic number, because the mean of its divisors is an integer number (130201255).

Almost surely, 2^260402509 is an apocalyptic number.

It is an amenable number.

260402509 is a deficient number, since it is larger than the sum of its proper divisors (1).

260402509 is an equidigital number, since it uses as much as digits as its factorization.

260402509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 260402509 is about 16136.9919439777. The cubic root of 260402509 is about 638.5796210212.

The spelling of 260402509 in words is "two hundred sixty million, four hundred two thousand, five hundred nine".