551320221221 has 16 divisors (see below), whose sum is σ = 694033686528. Its totient is φ = 425429290800.

The previous prime is 551320221197. The next prime is 551320221241. The reversal of 551320221221 is 122122023155.

It is a happy number.

551320221221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 551320221221 - 2¹⁴ = 551320204837 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (551320221241) 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, 34749365 + ... + 34765226.

It is an arithmetic number, because the mean of its divisors is an integer number (43377105408).

Almost surely, 2^551320221221 is an apocalyptic number.

It is an amenable number.

551320221221 is a deficient number, since it is larger than the sum of its proper divisors (142713465307).

551320221221 is a wasteful number, since it uses less digits than its factorization.

551320221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69514712.

The product of its (nonzero) digits is 2400, while the sum is 26.

Adding to 551320221221 its reverse (122122023155), we get a palindrome (673442244376).

The spelling of 551320221221 in words is "five hundred fifty-one billion, three hundred twenty million, two hundred twenty-one thousand, two hundred twenty-one".