213620261 has 2 divisors, whose sum is σ = 213620262. Its totient is φ = 213620260.

The previous prime is 213620207. The next prime is 213620371. The reversal of 213620261 is 162026312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 187416100 + 26204161 = 13690^2 + 5119^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213620261 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 (213620201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106810130 + 106810131.

It is an arithmetic number, because the mean of its divisors is an integer number (106810131).

Almost surely, 2^213620261 is an apocalyptic number.

It is an amenable number.

213620261 is a deficient number, since it is larger than the sum of its proper divisors (1).

213620261 is an equidigital number, since it uses as much as digits as its factorization.

213620261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 213620261 is about 14615.7538635542. The cubic root of 213620261 is about 597.7883959919.

Adding to 213620261 its reverse (162026312), we get a palindrome (375646573).

The spelling of 213620261 in words is "two hundred thirteen million, six hundred twenty thousand, two hundred sixty-one".