165615541 has 12 divisors (see below), whose sum is σ = 207475212. Its totient is φ = 131035968.

The previous prime is 165615511. The next prime is 165615553. The reversal of 165615541 is 145516561.

It can be written as a sum of positive squares in 2 ways, for example, as 12103441 + 153512100 = 3479^2 + 12390^2 .

It is not a de Polignac number, because 165615541 - 2⁵ = 165615509 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 165615497 and 165615506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165615511) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 129360 + ... + 130633.

It is an arithmetic number, because the mean of its divisors is an integer number (17289601).

Almost surely, 2^165615541 is an apocalyptic number.

It is an amenable number.

165615541 is a deficient number, since it is larger than the sum of its proper divisors (41859671).

165615541 is a wasteful number, since it uses less digits than its factorization.

165615541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260020 (or 260013 counting only the distinct ones).

The product of its digits is 18000, while the sum is 34.

The square root of 165615541 is about 12869.1701752677. The cubic root of 165615541 is about 549.1618539750.

The spelling of 165615541 in words is "one hundred sixty-five million, six hundred fifteen thousand, five hundred forty-one".