545501221 has 2 divisors, whose sum is σ = 545501222. Its totient is φ = 545501220.

The previous prime is 545501171. The next prime is 545501251. The reversal of 545501221 is 122105545.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 445800996 + 99700225 = 21114^2 + 9985^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-545501221 is a prime.

It is a super-2 number, since 2×545501221² = 595143164224981682, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (545501251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 272750610 + 272750611.

It is an arithmetic number, because the mean of its divisors is an integer number (272750611).

Almost surely, 2^545501221 is an apocalyptic number.

It is an amenable number.

545501221 is a deficient number, since it is larger than the sum of its proper divisors (1).

545501221 is an equidigital number, since it uses as much as digits as its factorization.

545501221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2000, while the sum is 25.

The square root of 545501221 is about 23355.9675671979. The cubic root of 545501221 is about 817.0812456938.

Adding to 545501221 its reverse (122105545), we get a palindrome (667606766).

The spelling of 545501221 in words is "five hundred forty-five million, five hundred one thousand, two hundred twenty-one".