165642541 has 2 divisors, whose sum is σ = 165642542. Its totient is φ = 165642540.

The previous prime is 165642479. The next prime is 165642553. The reversal of 165642541 is 145246561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 124233316 + 41409225 = 11146^2 + 6435^2 .

It is a cyclic number.

It is not a de Polignac number, because 165642541 - 2⁷ = 165642413 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 165642497 and 165642506.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165642571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82821270 + 82821271.

It is an arithmetic number, because the mean of its divisors is an integer number (82821271).

Almost surely, 2^165642541 is an apocalyptic number.

It is an amenable number.

165642541 is a deficient number, since it is larger than the sum of its proper divisors (1).

165642541 is an equidigital number, since it uses as much as digits as its factorization.

165642541 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28800, while the sum is 34.

The square root of 165642541 is about 12870.2191512033. The cubic root of 165642541 is about 549.1916953057.

The spelling of 165642541 in words is "one hundred sixty-five million, six hundred forty-two thousand, five hundred forty-one".