261951941 has 2 divisors, whose sum is σ = 261951942. Its totient is φ = 261951940.

The previous prime is 261951919. The next prime is 261951947. The reversal of 261951941 is 149159162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 236236900 + 25715041 = 15370^2 + 5071^2 .

It is a cyclic number.

It is not a de Polignac number, because 261951941 - 2¹⁰ = 261950917 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261951895 and 261951904.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261951947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130975970 + 130975971.

It is an arithmetic number, because the mean of its divisors is an integer number (130975971).

Almost surely, 2^261951941 is an apocalyptic number.

It is an amenable number.

261951941 is a deficient number, since it is larger than the sum of its proper divisors (1).

261951941 is an equidigital number, since it uses as much as digits as its factorization.

261951941 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19440, while the sum is 38.

The square root of 261951941 is about 16184.9294406865. The cubic root of 261951941 is about 639.8436637997.

The spelling of 261951941 in words is "two hundred sixty-one million, nine hundred fifty-one thousand, nine hundred forty-one".