261226957 has 2 divisors, whose sum is σ = 261226958. Its totient is φ = 261226956.

The previous prime is 261226921. The next prime is 261226967. The reversal of 261226957 is 759622162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 244953801 + 16273156 = 15651^2 + 4034^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261226957 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261226907) 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, 130613478 + 130613479.

It is an arithmetic number, because the mean of its divisors is an integer number (130613479).

Almost surely, 2^261226957 is an apocalyptic number.

It is an amenable number.

261226957 is a deficient number, since it is larger than the sum of its proper divisors (1).

261226957 is an equidigital number, since it uses as much as digits as its factorization.

261226957 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 40.

The square root of 261226957 is about 16162.5170378874. The cubic root of 261226957 is about 639.2528365649.

The spelling of 261226957 in words is "two hundred sixty-one million, two hundred twenty-six thousand, nine hundred fifty-seven".