213401609 has 2 divisors, whose sum is σ = 213401610. Its totient is φ = 213401608.

The previous prime is 213401599. The next prime is 213401611. The reversal of 213401609 is 906104312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 199600384 + 13801225 = 14128^2 + 3715^2 .

It is a cyclic number.

It is not a de Polignac number, because 213401609 - 2⁴ = 213401593 is a prime.

Together with 213401611, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (213401689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106700804 + 106700805.

It is an arithmetic number, because the mean of its divisors is an integer number (106700805).

Almost surely, 2^213401609 is an apocalyptic number.

It is an amenable number.

213401609 is a deficient number, since it is larger than the sum of its proper divisors (1).

213401609 is an equidigital number, since it uses as much as digits as its factorization.

213401609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 213401609 is about 14608.2719375017. The cubic root of 213401609 is about 597.5843700121.

The spelling of 213401609 in words is "two hundred thirteen million, four hundred one thousand, six hundred nine".