551011309 has 4 divisors (see below), whose sum is σ = 551059740. Its totient is φ = 550962880.

The previous prime is 551011303. The next prime is 551011319. The reversal of 551011309 is 903110155.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 903110155 = 5 ⋅180622031.

It can be written as a sum of positive squares in 2 ways, for example, as 419840100 + 131171209 = 20490^2 + 11453^2 .

It is a cyclic number.

It is not a de Polignac number, because 551011309 - 2³ = 551011301 is a prime.

It is a super-2 number, since 2×551011309² = 607226925291786962, 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 (551011301) 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, 3189 + ... + 33349.

It is an arithmetic number, because the mean of its divisors is an integer number (137764935).

Almost surely, 2^551011309 is an apocalyptic number.

It is an amenable number.

551011309 is a deficient number, since it is larger than the sum of its proper divisors (48431).

551011309 is a wasteful number, since it uses less digits than its factorization.

551011309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48430.

The product of its (nonzero) digits is 675, while the sum is 25.

The square root of 551011309 is about 23473.6300771738. The cubic root of 551011309 is about 819.8231370491.

The spelling of 551011309 in words is "five hundred fifty-one million, eleven thousand, three hundred nine".