165146621 has 2 divisors, whose sum is σ = 165146622. Its totient is φ = 165146620.

The previous prime is 165146593. The next prime is 165146623. The reversal of 165146621 is 126641561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 121771225 + 43375396 = 11035^2 + 6586^2 .

It is an emirp because it is prime and its reverse (126641561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165146621 - 2¹⁴ = 165130237 is a prime.

Together with 165146623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165146623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82573310 + 82573311.

It is an arithmetic number, because the mean of its divisors is an integer number (82573311).

Almost surely, 2^165146621 is an apocalyptic number.

It is an amenable number.

165146621 is a deficient number, since it is larger than the sum of its proper divisors (1).

165146621 is an equidigital number, since it uses as much as digits as its factorization.

165146621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8640, while the sum is 32.

The square root of 165146621 is about 12850.9385260377. The cubic root of 165146621 is about 548.6430693312.

The spelling of 165146621 in words is "one hundred sixty-five million, one hundred forty-six thousand, six hundred twenty-one".