551115511 has 4 divisors (see below), whose sum is σ = 551180592. Its totient is φ = 551050432.

The previous prime is 551115473. The next prime is 551115527. The reversal of 551115511 is 115511155.

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: 115511155 = 5 ⋅23102231.

It is a cyclic number.

It is not a de Polignac number, because 551115511 - 2²¹ = 549018359 is a prime.

It is a super-2 number, since 2×551115511² = 607456612929582242, which contains 22 as substring.

It is a Duffinian number.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (551115211) 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, 17530 + ... + 37543.

It is an arithmetic number, because the mean of its divisors is an integer number (137795148).

Almost surely, 2^551115511 is an apocalyptic number.

551115511 is a deficient number, since it is larger than the sum of its proper divisors (65081).

551115511 is a wasteful number, since it uses less digits than its factorization.

551115511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65080.

The product of its digits is 625, while the sum is 25.

The square root of 551115511 is about 23475.8495266944. The cubic root of 551115511 is about 819.8748128343.

Adding to 551115511 its reverse (115511155), we get a palindrome (666626666).

The spelling of 551115511 in words is "five hundred fifty-one million, one hundred fifteen thousand, five hundred eleven".