221266541 has 2 divisors, whose sum is σ = 221266542. Its totient is φ = 221266540.

The previous prime is 221266531. The next prime is 221266613. The reversal of 221266541 is 145662122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 217444516 + 3822025 = 14746^2 + 1955^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221266541 is a prime.

It is a super-2 number, since 2×221266541² = 97917764332209362, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221266531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110633270 + 110633271.

It is an arithmetic number, because the mean of its divisors is an integer number (110633271).

Almost surely, 2^221266541 is an apocalyptic number.

It is an amenable number.

221266541 is a deficient number, since it is larger than the sum of its proper divisors (1).

221266541 is an equidigital number, since it uses as much as digits as its factorization.

221266541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5760, while the sum is 29.

The square root of 221266541 is about 14875.0307898841. The cubic root of 221266541 is about 604.8373225620.

The spelling of 221266541 in words is "two hundred twenty-one million, two hundred sixty-six thousand, five hundred forty-one".