261922513 has 2 divisors, whose sum is σ = 261922514. Its totient is φ = 261922512.

The previous prime is 261922501. The next prime is 261922517. The reversal of 261922513 is 315229162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 134954689 + 126967824 = 11617^2 + 11268^2 .

It is a cyclic number.

It is not a de Polignac number, because 261922513 - 2¹⁷ = 261791441 is a prime.

It is not a weakly prime, because it can be changed into another prime (261922517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130961256 + 130961257.

It is an arithmetic number, because the mean of its divisors is an integer number (130961257).

Almost surely, 2^261922513 is an apocalyptic number.

It is an amenable number.

261922513 is a deficient number, since it is larger than the sum of its proper divisors (1).

261922513 is an equidigital number, since it uses as much as digits as its factorization.

261922513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 31.

The square root of 261922513 is about 16184.0202978123. The cubic root of 261922513 is about 639.8197026303.

The spelling of 261922513 in words is "two hundred sixty-one million, nine hundred twenty-two thousand, five hundred thirteen".