261165170237 has 2 divisors, whose sum is σ = 261165170238. Its totient is φ = 261165170236.

The previous prime is 261165170197. The next prime is 261165170281. The reversal of 261165170237 is 732071561162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 181539053476 + 79626116761 = 426074^2 + 282181^2 .

It is a cyclic number.

It is not a de Polignac number, because 261165170237 - 2¹⁸ = 261164908093 is a prime.

It is a super-2 number, since 2×261165170237² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 261165170194 and 261165170203.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261165170537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130582585118 + 130582585119.

It is an arithmetic number, because the mean of its divisors is an integer number (130582585119).

Almost surely, 2^261165170237 is an apocalyptic number.

It is an amenable number.

261165170237 is a deficient number, since it is larger than the sum of its proper divisors (1).

261165170237 is an equidigital number, since it uses as much as digits as its factorization.

261165170237 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 105840, while the sum is 41.

The spelling of 261165170237 in words is "two hundred sixty-one billion, one hundred sixty-five million, one hundred seventy thousand, two hundred thirty-seven".