165551156144531 has 4 divisors (see below), whose sum is σ = 174264374889000. Its totient is φ = 156837937400064.

The previous prime is 165551156144519. The next prime is 165551156144533. The reversal of 165551156144531 is 135441651155561.

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

It is a cyclic number.

It is not a de Polignac number, because 165551156144531 - 2⁶ = 165551156144467 is a prime.

It is a super-2 number, since 2×165551156144531² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165551156144533) 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 3 ways as a sum of consecutive naturals, for example, 4356609372206 + ... + 4356609372243.

It is an arithmetic number, because the mean of its divisors is an integer number (43566093722250).

Almost surely, 2^{165551156144531} is an apocalyptic number.

165551156144531 is a deficient number, since it is larger than the sum of its proper divisors (8713218744469).

165551156144531 is an equidigital number, since it uses as much as digits as its factorization.

165551156144531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8713218744468.

The product of its digits is 5400000, while the sum is 53.

The spelling of 165551156144531 in words is "one hundred sixty-five trillion, five hundred fifty-one billion, one hundred fifty-six million, one hundred forty-four thousand, five hundred thirty-one".