551115021 has 4 divisors (see below), whose sum is σ = 734820032. Its totient is φ = 367410012.

The previous prime is 551115017. The next prime is 551115023. The reversal of 551115021 is 120511155.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 551115021 - 2² = 551115017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (551115023) 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 3 ways as a sum of consecutive naturals, for example, 91852501 + ... + 91852506.

It is an arithmetic number, because the mean of its divisors is an integer number (183705008).

Almost surely, 2^551115021 is an apocalyptic number.

It is an amenable number.

551115021 is a deficient number, since it is larger than the sum of its proper divisors (183705011).

551115021 is a wasteful number, since it uses less digits than its factorization.

551115021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183705010.

The product of its (nonzero) digits is 250, while the sum is 21.

The square root of 551115021 is about 23475.8390904351. The cubic root of 551115021 is about 819.8745698490.

Adding to 551115021 its reverse (120511155), we get a palindrome (671626176).

The spelling of 551115021 in words is "five hundred fifty-one million, one hundred fifteen thousand, twenty-one".