165520051 has 4 divisors (see below), whose sum is σ = 165576400. Its totient is φ = 165463704.

The previous prime is 165520049. The next prime is 165520111. The reversal of 165520051 is 150025561.

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 165520051 - 2¹ = 165520049 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165519998 and 165520025.

It is not an unprimeable number, because it can be changed into a prime (165520021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23511 + ... + 29728.

It is an arithmetic number, because the mean of its divisors is an integer number (41394100).

Almost surely, 2^165520051 is an apocalyptic number.

165520051 is a deficient number, since it is larger than the sum of its proper divisors (56349).

165520051 is an equidigital number, since it uses as much as digits as its factorization.

165520051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56348.

The product of its (nonzero) digits is 1500, while the sum is 25.

The square root of 165520051 is about 12865.4596109117. The cubic root of 165520051 is about 549.0562891092.

The spelling of 165520051 in words is "one hundred sixty-five million, five hundred twenty thousand, fifty-one".