165954993 has 4 divisors (see below), whose sum is σ = 221273328. Its totient is φ = 110636660.

The previous prime is 165954991. The next prime is 165955001. The reversal of 165954993 is 399459561.

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.

It is a cyclic number.

It is not a de Polignac number, because 165954993 - 2¹ = 165954991 is a prime.

It is not an unprimeable number, because it can be changed into a prime (165954991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27659163 + ... + 27659168.

It is an arithmetic number, because the mean of its divisors is an integer number (55318332).

Almost surely, 2^165954993 is an apocalyptic number.

It is an amenable number.

165954993 is a deficient number, since it is larger than the sum of its proper divisors (55318335).

165954993 is an equidigital number, since it uses as much as digits as its factorization.

165954993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55318334.

The product of its digits is 1312200, while the sum is 51.

The square root of 165954993 is about 12882.3519979855. The cubic root of 165954993 is about 549.5367923672.

The spelling of 165954993 in words is "one hundred sixty-five million, nine hundred fifty-four thousand, nine hundred ninety-three".