261967470409 has 2 divisors, whose sum is σ = 261967470410. Its totient is φ = 261967470408.

The previous prime is 261967470353. The next prime is 261967470439. The reversal of 261967470409 is 904074769162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 191469255184 + 70498215225 = 437572^2 + 265515^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261967470409 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 261967470409.

It is not a weakly prime, because it can be changed into another prime (261967470439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130983735204 + 130983735205.

It is an arithmetic number, because the mean of its divisors is an integer number (130983735205).

Almost surely, 2^261967470409 is an apocalyptic number.

It is an amenable number.

261967470409 is a deficient number, since it is larger than the sum of its proper divisors (1).

261967470409 is an equidigital number, since it uses as much as digits as its factorization.

261967470409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4572288, while the sum is 55.

The spelling of 261967470409 in words is "two hundred sixty-one billion, nine hundred sixty-seven million, four hundred seventy thousand, four hundred nine".