165564641 has 4 divisors (see below), whose sum is σ = 180615984. Its totient is φ = 150513300.

The previous prime is 165564593. The next prime is 165564643. The reversal of 165564641 is 146465561.

It is a happy number.

165564641 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 146465561 = 11 ⋅13315051.

It is a cyclic number.

It is not a de Polignac number, because 165564641 - 2²² = 161370337 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165564595 and 165564604.

It is not an unprimeable number, because it can be changed into a prime (165564643) 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, 7525655 + ... + 7525676.

It is an arithmetic number, because the mean of its divisors is an integer number (45153996).

Almost surely, 2^165564641 is an apocalyptic number.

165564641 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

165564641 is a deficient number, since it is larger than the sum of its proper divisors (15051343).

165564641 is a wasteful number, since it uses less digits than its factorization.

165564641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15051342.

The product of its digits is 86400, while the sum is 38.

The square root of 165564641 is about 12867.1924288090. The cubic root of 165564641 is about 549.1055887190.

The spelling of 165564641 in words is "one hundred sixty-five million, five hundred sixty-four thousand, six hundred forty-one".