165251653789 has 4 divisors (see below), whose sum is σ = 174972339324. Its totient is φ = 155530968256.

The previous prime is 165251653757. The next prime is 165251653817. The reversal of 165251653789 is 987356152561.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 99771961689 + 65479692100 = 315867^2 + 255890^2 .

It is a cyclic number.

It is not a de Polignac number, because 165251653789 - 2⁵ = 165251653757 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165251653739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4860342742 + ... + 4860342775.

It is an arithmetic number, because the mean of its divisors is an integer number (43743084831).

Almost surely, 2^165251653789 is an apocalyptic number.

It is an amenable number.

165251653789 is a deficient number, since it is larger than the sum of its proper divisors (9720685535).

165251653789 is an equidigital number, since it uses as much as digits as its factorization.

165251653789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9720685534.

The product of its digits is 13608000, while the sum is 58.

The spelling of 165251653789 in words is "one hundred sixty-five billion, two hundred fifty-one million, six hundred fifty-three thousand, seven hundred eighty-nine".