165019433388121 has 27 divisors (see below), whose sum is σ = 179502207710007. Its totient is φ = 151636109514240.

The previous prime is 165019433388101. The next prime is 165019433388143. The reversal of 165019433388121 is 121883334910561.

The square root of 165019433388121 is 12845989.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 13 ways, for example, as 90096905979721 + 74922527408400 = 9491939^2 + 8655780^2 .

It is not a de Polignac number, because 165019433388121 - 2³⁹ = 164469677574233 is a prime.

It is a super-2 number, since 2×165019433388121² (a number of 29 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (165019433388101) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 38910498561 + ... + 38910502801.

Almost surely, 2^{165019433388121} is an apocalyptic number.

165019433388121 is the 12845989-th square number.

165019433388121 is the 6422995-th centered octagonal number.

It is an amenable number.

165019433388121 is a deficient number, since it is larger than the sum of its proper divisors (14482774321886).

165019433388121 is an frugal number, since it uses more digits than its factorization.

165019433388121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8974 (or 4487 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 55.

The spelling of 165019433388121 in words is "one hundred sixty-five trillion, nineteen billion, four hundred thirty-three million, three hundred eighty-eight thousand, one hundred twenty-one".