261713161 has 2 divisors, whose sum is σ = 261713162. Its totient is φ = 261713160.

The previous prime is 261713131. The next prime is 261713213. The reversal of 261713161 is 161317162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 177422400 + 84290761 = 13320^2 + 9181^2 .

It is a cyclic number.

It is not a de Polignac number, because 261713161 - 2¹³ = 261704969 is a prime.

It is a super-2 number, since 2×261713161² = 136987557281223842, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (261713131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130856580 + 130856581.

It is an arithmetic number, because the mean of its divisors is an integer number (130856581).

Almost surely, 2^261713161 is an apocalyptic number.

It is an amenable number.

261713161 is a deficient number, since it is larger than the sum of its proper divisors (1).

261713161 is an equidigital number, since it uses as much as digits as its factorization.

261713161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1512, while the sum is 28.

The square root of 261713161 is about 16177.5511434827. The cubic root of 261713161 is about 639.6491900662.

The spelling of 261713161 in words is "two hundred sixty-one million, seven hundred thirteen thousand, one hundred sixty-one".