165337738781 has 8 divisors (see below), whose sum is σ = 168478826040. Its totient is φ = 162197448192.

The previous prime is 165337738759. The next prime is 165337738789. The reversal of 165337738781 is 187837733561.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6046681 + 165331692100 = 2459^2 + 406610^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 165337738781 - 2⁶ = 165337738717 is a prime.

It is a super-2 number, since 2×165337738781² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 165337738781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165337738789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 228485 + ... + 618773.

It is an arithmetic number, because the mean of its divisors is an integer number (21059853255).

Almost surely, 2^165337738781 is an apocalyptic number.

It is an amenable number.

165337738781 is a deficient number, since it is larger than the sum of its proper divisors (3141087259).

165337738781 is an equidigital number, since it uses as much as digits as its factorization.

165337738781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 398335.

The product of its digits is 17781120, while the sum is 59.

The spelling of 165337738781 in words is "one hundred sixty-five billion, three hundred thirty-seven million, seven hundred thirty-eight thousand, seven hundred eighty-one".