261441948457 has 2 divisors, whose sum is σ = 261441948458. Its totient is φ = 261441948456.

The previous prime is 261441948421. The next prime is 261441948463. The reversal of 261441948457 is 754849144162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 251927701776 + 9514246681 = 501924^2 + 97541^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261441948457 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261441948398 and 261441948407.

It is not a weakly prime, because it can be changed into another prime (261441948857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130720974228 + 130720974229.

It is an arithmetic number, because the mean of its divisors is an integer number (130720974229).

Almost surely, 2^261441948457 is an apocalyptic number.

It is an amenable number.

261441948457 is a deficient number, since it is larger than the sum of its proper divisors (1).

261441948457 is an equidigital number, since it uses as much as digits as its factorization.

261441948457 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7741440, while the sum is 55.

The spelling of 261441948457 in words is "two hundred sixty-one billion, four hundred forty-one million, nine hundred forty-eight thousand, four hundred fifty-seven".