165641213 has 2 divisors, whose sum is σ = 165641214. Its totient is φ = 165641212.

The previous prime is 165641197. The next prime is 165641233. The reversal of 165641213 is 312146561.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 116683204 + 48958009 = 10802^2 + 6997^2 .

It is an emirp because it is prime and its reverse (312146561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165641213 - 2⁴ = 165641197 is a prime.

It is a super-2 number, since 2×165641213² = 54874022888222738, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165641233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82820606 + 82820607.

It is an arithmetic number, because the mean of its divisors is an integer number (82820607).

Almost surely, 2^165641213 is an apocalyptic number.

It is an amenable number.

165641213 is a deficient number, since it is larger than the sum of its proper divisors (1).

165641213 is an equidigital number, since it uses as much as digits as its factorization.

165641213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 29.

The square root of 165641213 is about 12870.1675591268. The cubic root of 165641213 is about 549.1902276302.

Adding to 165641213 its reverse (312146561), we get a palindrome (477787774).

The spelling of 165641213 in words is "one hundred sixty-five million, six hundred forty-one thousand, two hundred thirteen".