165124551 has 4 divisors (see below), whose sum is σ = 220166072. Its totient is φ = 110083032.

The previous prime is 165124543. The next prime is 165124559. The reversal of 165124551 is 155421561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 155421561 = 3 ⋅51807187.

It is an interprime number because it is at equal distance from previous prime (165124543) and next prime (165124559).

It is not a de Polignac number, because 165124551 - 2³ = 165124543 is a prime.

It is a super-2 number, since 2×165124551² = 54532234685903202, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165124559) 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, 27520756 + ... + 27520761.

It is an arithmetic number, because the mean of its divisors is an integer number (55041518).

Almost surely, 2^165124551 is an apocalyptic number.

165124551 is a deficient number, since it is larger than the sum of its proper divisors (55041521).

165124551 is an equidigital number, since it uses as much as digits as its factorization.

165124551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55041520.

The product of its digits is 6000, while the sum is 30.

The square root of 165124551 is about 12850.0798051997. The cubic root of 165124551 is about 548.6186282378.

The spelling of 165124551 in words is "one hundred sixty-five million, one hundred twenty-four thousand, five hundred fifty-one".