165188825261 has 2 divisors, whose sum is σ = 165188825262. Its totient is φ = 165188825260.

The previous prime is 165188825227. The next prime is 165188825353. The reversal of 165188825261 is 162528881561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 158100869161 + 7087956100 = 397619^2 + 84190^2 .

It is a cyclic number.

It is not a de Polignac number, because 165188825261 - 2¹⁴ = 165188808877 is a prime.

It is a super-2 number, since 2×165188825261² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165188825161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82594412630 + 82594412631.

It is an arithmetic number, because the mean of its divisors is an integer number (82594412631).

Almost surely, 2^165188825261 is an apocalyptic number.

It is an amenable number.

165188825261 is a deficient number, since it is larger than the sum of its proper divisors (1).

165188825261 is an equidigital number, since it uses as much as digits as its factorization.

165188825261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1843200, while the sum is 53.

The spelling of 165188825261 in words is "one hundred sixty-five billion, one hundred eighty-eight million, eight hundred twenty-five thousand, two hundred sixty-one".