213555137 has 2 divisors, whose sum is σ = 213555138. Its totient is φ = 213555136.

The previous prime is 213555127. The next prime is 213555151. The reversal of 213555137 is 731555312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 209409841 + 4145296 = 14471^2 + 2036^2 .

It is a cyclic number.

It is not a de Polignac number, because 213555137 - 2²⁰ = 212506561 is a prime.

It is not a weakly prime, because it can be changed into another prime (213555127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106777568 + 106777569.

It is an arithmetic number, because the mean of its divisors is an integer number (106777569).

Almost surely, 2^213555137 is an apocalyptic number.

It is an amenable number.

213555137 is a deficient number, since it is larger than the sum of its proper divisors (1).

213555137 is an equidigital number, since it uses as much as digits as its factorization.

213555137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15750, while the sum is 32.

The square root of 213555137 is about 14613.5258237018. The cubic root of 213555137 is about 597.7276428154.

The spelling of 213555137 in words is "two hundred thirteen million, five hundred fifty-five thousand, one hundred thirty-seven".