165523120551 has 12 divisors (see below), whose sum is σ = 241282429960. Its totient is φ = 109336372560.

The previous prime is 165523120537. The next prime is 165523120583. The reversal of 165523120551 is 155021325561.

165523120551 is a `hidden beast` number, since 1 + 6 + 5 + 52 + 31 + 20 + 551 = 666.

165523120551 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 165523120551 - 2¹⁴ = 165523104167 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165523120051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 84363505 + ... + 84365466.

Almost surely, 2^165523120551 is an apocalyptic number.

165523120551 is a deficient number, since it is larger than the sum of its proper divisors (75759309409).

165523120551 is a wasteful number, since it uses less digits than its factorization.

165523120551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168729086 (or 168729083 counting only the distinct ones).

The product of its (nonzero) digits is 45000, while the sum is 36.

The spelling of 165523120551 in words is "one hundred sixty-five billion, five hundred twenty-three million, one hundred twenty thousand, five hundred fifty-one".