3551123221 has 2 divisors, whose sum is σ = 3551123222. Its totient is φ = 3551123220.

The previous prime is 3551123209. The next prime is 3551123243. The reversal of 3551123221 is 1223211553.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1817316900 + 1733806321 = 42630^2 + 41639^2 .

It is a cyclic number.

It is not a de Polignac number, because 3551123221 - 2⁵ = 3551123189 is a prime.

It is a super-2 number, since 2×3551123221² = 25220952261450829682, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3551121221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1775561610 + 1775561611.

It is an arithmetic number, because the mean of its divisors is an integer number (1775561611).

Almost surely, 2^3551123221 is an apocalyptic number.

It is an amenable number.

3551123221 is a deficient number, since it is larger than the sum of its proper divisors (1).

3551123221 is an equidigital number, since it uses as much as digits as its factorization.

3551123221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1800, while the sum is 25.

The square root of 3551123221 is about 59591.3015548410. The cubic root of 3551123221 is about 1525.6511734553.

Adding to 3551123221 its reverse (1223211553), we get a palindrome (4774334774).

The spelling of 3551123221 in words is "three billion, five hundred fifty-one million, one hundred twenty-three thousand, two hundred twenty-one".