551661065 has 4 divisors (see below), whose sum is σ = 661993284. Its totient is φ = 441328848.

The previous prime is 551661059. The next prime is 551661107. The reversal of 551661065 is 560166155.

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 62853184 + 488807881 = 7928^2 + 22109^2 .

It is a cyclic number.

It is not a de Polignac number, because 551661065 - 2⁶ = 551661001 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55166102 + ... + 55166111.

It is an arithmetic number, because the mean of its divisors is an integer number (165498321).

Almost surely, 2^551661065 is an apocalyptic number.

It is an amenable number.

551661065 is a deficient number, since it is larger than the sum of its proper divisors (110332219).

551661065 is a wasteful number, since it uses less digits than its factorization.

551661065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110332218.

The product of its (nonzero) digits is 27000, while the sum is 35.

The square root of 551661065 is about 23487.4661255743. The cubic root of 551661065 is about 820.1452573328.

The spelling of 551661065 in words is "five hundred fifty-one million, six hundred sixty-one thousand, sixty-five".