165816645 has 16 divisors (see below), whose sum is σ = 265636800. Its totient is φ = 88325504.

The previous prime is 165816631. The next prime is 165816659. The reversal of 165816645 is 546618561.

It is an interprime number because it is at equal distance from previous prime (165816631) and next prime (165816659).

It is a cyclic number.

It is not a de Polignac number, because 165816645 - 2¹³ = 165808453 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 165816597 and 165816606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6406 + ... + 19304.

It is an arithmetic number, because the mean of its divisors is an integer number (16602300).

Almost surely, 2^165816645 is an apocalyptic number.

165816645 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

165816645 is a deficient number, since it is larger than the sum of its proper divisors (99820155).

165816645 is a wasteful number, since it uses less digits than its factorization.

165816645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13764.

The product of its digits is 172800, while the sum is 42.

The square root of 165816645 is about 12876.9812067891. The cubic root of 165816645 is about 549.3840432167.

The spelling of 165816645 in words is "one hundred sixty-five million, eight hundred sixteen thousand, six hundred forty-five".