1261492513 has 2 divisors, whose sum is σ = 1261492514. Its totient is φ = 1261492512.

The previous prime is 1261492501. The next prime is 1261492567. The reversal of 1261492513 is 3152941621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 896223969 + 365268544 = 29937^2 + 19112^2 .

It is a cyclic number.

It is not a de Polignac number, because 1261492513 - 2⁵ = 1261492481 is a prime.

It is not a weakly prime, because it can be changed into another prime (1261492313) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 630746256 + 630746257.

It is an arithmetic number, because the mean of its divisors is an integer number (630746257).

Almost surely, 2^1261492513 is an apocalyptic number.

It is an amenable number.

1261492513 is a deficient number, since it is larger than the sum of its proper divisors (1).

1261492513 is an equidigital number, since it uses as much as digits as its factorization.

1261492513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12960, while the sum is 34.

The square root of 1261492513 is about 35517.4958717531. The cubic root of 1261492513 is about 1080.5085947594.

The spelling of 1261492513 in words is "one billion, two hundred sixty-one million, four hundred ninety-two thousand, five hundred thirteen".