215644141 has 2 divisors, whose sum is σ = 215644142. Its totient is φ = 215644140.

The previous prime is 215644139. The next prime is 215644147. The reversal of 215644141 is 141446512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 184172041 + 31472100 = 13571^2 + 5610^2 .

It is a cyclic number.

It is not a de Polignac number, because 215644141 - 2¹ = 215644139 is a prime.

Together with 215644139, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215644147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107822070 + 107822071.

It is an arithmetic number, because the mean of its divisors is an integer number (107822071).

Almost surely, 2^215644141 is an apocalyptic number.

215644141 is the 9288-th centered pentagonal number.

It is an amenable number.

215644141 is a deficient number, since it is larger than the sum of its proper divisors (1).

215644141 is an equidigital number, since it uses as much as digits as its factorization.

215644141 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3840, while the sum is 28.

The square root of 215644141 is about 14684.8268971752. The cubic root of 215644141 is about 599.6703198107.

The spelling of 215644141 in words is "two hundred fifteen million, six hundred forty-four thousand, one hundred forty-one".