261854969 has 2 divisors, whose sum is σ = 261854970. Its totient is φ = 261854968.

The previous prime is 261854947. The next prime is 261855019. The reversal of 261854969 is 969458162.

It is an a-pointer prime, because the next prime (261855019) can be obtained adding 261854969 to its sum of digits (50).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 188101225 + 73753744 = 13715^2 + 8588^2 .

It is a cyclic number.

It is not a de Polignac number, because 261854969 - 2²⁰ = 260806393 is a prime.

It is a super-2 number, since 2×261854969² = 137136049579981922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (261854909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130927484 + 130927485.

It is an arithmetic number, because the mean of its divisors is an integer number (130927485).

Almost surely, 2^261854969 is an apocalyptic number.

It is an amenable number.

261854969 is a deficient number, since it is larger than the sum of its proper divisors (1).

261854969 is an equidigital number, since it uses as much as digits as its factorization.

261854969 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 933120, while the sum is 50.

The square root of 261854969 is about 16181.9334135325. The cubic root of 261854969 is about 639.7646994707.

The spelling of 261854969 in words is "two hundred sixty-one million, eight hundred fifty-four thousand, nine hundred sixty-nine".