221031413 has 2 divisors, whose sum is σ = 221031414. Its totient is φ = 221031412.

The previous prime is 221031409. The next prime is 221031443. The reversal of 221031413 is 314130122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 124166449 + 96864964 = 11143^2 + 9842^2 .

It is a cyclic number.

It is not a de Polignac number, because 221031413 - 2² = 221031409 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221031391 and 221031400.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221031443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110515706 + 110515707.

It is an arithmetic number, because the mean of its divisors is an integer number (110515707).

Almost surely, 2^221031413 is an apocalyptic number.

It is an amenable number.

221031413 is a deficient number, since it is larger than the sum of its proper divisors (1).

221031413 is an equidigital number, since it uses as much as digits as its factorization.

221031413 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 221031413 is about 14867.1252433011. The cubic root of 221031413 is about 604.6230039796.

Adding to 221031413 its reverse (314130122), we get a palindrome (535161535).

The spelling of 221031413 in words is "two hundred twenty-one million, thirty-one thousand, four hundred thirteen".