551345221 has 16 divisors (see below), whose sum is σ = 637561600. Its totient is φ = 467026560.

The previous prime is 551345161. The next prime is 551345231. The reversal of 551345221 is 122543155.

It is not a de Polignac number, because 551345221 - 2¹³ = 551337029 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 551345221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (551345231) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 217441 + ... + 219961.

It is an arithmetic number, because the mean of its divisors is an integer number (39847600).

Almost surely, 2^551345221 is an apocalyptic number.

It is an amenable number.

551345221 is a deficient number, since it is larger than the sum of its proper divisors (86216379).

551345221 is a wasteful number, since it uses less digits than its factorization.

551345221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2884.

The product of its digits is 6000, while the sum is 28.

The square root of 551345221 is about 23480.7414916991. The cubic root of 551345221 is about 819.9887074590.

Adding to 551345221 its reverse (122543155), we get a palindrome (673888376).

The spelling of 551345221 in words is "five hundred fifty-one million, three hundred forty-five thousand, two hundred twenty-one".