551720165 has 4 divisors (see below), whose sum is σ = 662064204. Its totient is φ = 441376128.

The previous prime is 551720153. The next prime is 551720179. The reversal of 551720165 is 561027155.

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

It can be written as a sum of positive squares in 2 ways, for example, as 171976996 + 379743169 = 13114^2 + 19487^2 .

It is a cyclic number.

It is not a de Polignac number, because 551720165 - 2¹⁰ = 551719141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55172012 + ... + 55172021.

It is an arithmetic number, because the mean of its divisors is an integer number (165516051).

Almost surely, 2^551720165 is an apocalyptic number.

It is an amenable number.

551720165 is a deficient number, since it is larger than the sum of its proper divisors (110344039).

551720165 is a wasteful number, since it uses less digits than its factorization.

551720165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110344038.

The product of its (nonzero) digits is 10500, while the sum is 32.

The square root of 551720165 is about 23488.7242097139. The cubic root of 551720165 is about 820.1745439467.

The spelling of 551720165 in words is "five hundred fifty-one million, seven hundred twenty thousand, one hundred sixty-five".