213047581 has 2 divisors, whose sum is σ = 213047582. Its totient is φ = 213047580.

The previous prime is 213047579. The next prime is 213047633. The reversal of 213047581 is 185740312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 147987225 + 65060356 = 12165^2 + 8066^2 .

It is a cyclic number.

It is not a de Polignac number, because 213047581 - 2¹ = 213047579 is a prime.

It is a super-2 number, since 2×213047581² = 90778543539903122, which contains 22 as substring.

Together with 213047579, 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 (213041581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106523790 + 106523791.

It is an arithmetic number, because the mean of its divisors is an integer number (106523791).

Almost surely, 2^213047581 is an apocalyptic number.

It is an amenable number.

213047581 is a deficient number, since it is larger than the sum of its proper divisors (1).

213047581 is an equidigital number, since it uses as much as digits as its factorization.

213047581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 213047581 is about 14596.1495265018. The cubic root of 213047581 is about 597.2537278641.

Adding to 213047581 its reverse (185740312), we get a palindrome (398787893).

The spelling of 213047581 in words is "two hundred thirteen million, forty-seven thousand, five hundred eighty-one".