551661345 has 48 divisors (see below), whose sum is σ = 1001894400. Its totient is φ = 280425600.

The previous prime is 551661343. The next prime is 551661349. The reversal of 551661345 is 543166155.

551661345 is a `hidden beast` number, since 5 + 516 + 6 + 134 + 5 = 666.

It is not a de Polignac number, because 551661345 - 2¹ = 551661343 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (551661343) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 100420 + ... + 105770.

It is an arithmetic number, because the mean of its divisors is an integer number (20872800).

Almost surely, 2^551661345 is an apocalyptic number.

It is an amenable number.

551661345 is a deficient number, since it is larger than the sum of its proper divisors (450233055).

551661345 is a wasteful number, since it uses less digits than its factorization.

551661345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5470 (or 5467 counting only the distinct ones).

The product of its digits is 54000, while the sum is 36.

The square root of 551661345 is about 23487.4720861995. The cubic root of 551661345 is about 820.1453960899.

The spelling of 551661345 in words is "five hundred fifty-one million, six hundred sixty-one thousand, three hundred forty-five".