165702121647 has 4 divisors (see below), whose sum is σ = 220936162200. Its totient is φ = 110468081096.

The previous prime is 165702121639. The next prime is 165702121657. The reversal of 165702121647 is 746121207561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 746121207561 = 3 ⋅248707069187.

It is a cyclic number.

It is not a de Polignac number, because 165702121647 - 2³ = 165702121639 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 165702121599 and 165702121608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165702121657) 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, 27617020272 + ... + 27617020277.

It is an arithmetic number, because the mean of its divisors is an integer number (55234040550).

Almost surely, 2^165702121647 is an apocalyptic number.

165702121647 is a deficient number, since it is larger than the sum of its proper divisors (55234040553).

165702121647 is an equidigital number, since it uses as much as digits as its factorization.

165702121647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55234040552.

The product of its (nonzero) digits is 141120, while the sum is 42.

The spelling of 165702121647 in words is "one hundred sixty-five billion, seven hundred two million, one hundred twenty-one thousand, six hundred forty-seven".