165479921 has 4 divisors (see below), whose sum is σ = 175214052. Its totient is φ = 155745792.

The previous prime is 165479893. The next prime is 165479959. The reversal of 165479921 is 129974561.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 137007025 + 28472896 = 11705^2 + 5336^2 .

It is a cyclic number.

It is not a de Polignac number, because 165479921 - 2¹⁸ = 165217777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165479021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4867040 + ... + 4867073.

It is an arithmetic number, because the mean of its divisors is an integer number (43803513).

Almost surely, 2^165479921 is an apocalyptic number.

It is an amenable number.

165479921 is a deficient number, since it is larger than the sum of its proper divisors (9734131).

165479921 is an equidigital number, since it uses as much as digits as its factorization.

165479921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9734130.

The product of its digits is 136080, while the sum is 44.

The square root of 165479921 is about 12863.8999141007. The cubic root of 165479921 is about 549.0119129955.

The spelling of 165479921 in words is "one hundred sixty-five million, four hundred seventy-nine thousand, nine hundred twenty-one".