213649 has 2 divisors, whose sum is σ = 213650. Its totient is φ = 213648.

The previous prime is 213641. The next prime is 213659. The reversal of 213649 is 946312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 176400 + 37249 = 420^2 + 193^2 .

It is a cyclic number.

It is not a de Polignac number, because 213649 - 2³ = 213641 is a prime.

It is not a weakly prime, because it can be changed into another prime (213641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106824 + 106825.

It is an arithmetic number, because the mean of its divisors is an integer number (106825).

2²¹³⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

213649 is a deficient number, since it is larger than the sum of its proper divisors (1).

213649 is an equidigital number, since it uses as much as digits as its factorization.

213649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 25.

The square root of 213649 is about 462.2218082263. The cubic root of 213649 is about 59.7815202236.

The spelling of 213649 in words is "two hundred thirteen thousand, six hundred forty-nine".