220001261 has 2 divisors, whose sum is σ = 220001262. Its totient is φ = 220001260.

The previous prime is 220001237. The next prime is 220001273. The reversal of 220001261 is 162100022.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 219928900 + 72361 = 14830^2 + 269^2 .

It is a cyclic number.

It is not a de Polignac number, because 220001261 - 2¹⁰ = 220000237 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (220001231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110000630 + 110000631.

It is an arithmetic number, because the mean of its divisors is an integer number (110000631).

Almost surely, 2^220001261 is an apocalyptic number.

It is an amenable number.

220001261 is a deficient number, since it is larger than the sum of its proper divisors (1).

220001261 is an equidigital number, since it uses as much as digits as its factorization.

220001261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 220001261 is about 14832.4394824317. The cubic root of 220001261 is about 603.6822270743.

Adding to 220001261 its reverse (162100022), we get a palindrome (382101283).

The spelling of 220001261 in words is "two hundred twenty million, one thousand, two hundred sixty-one".