221021010019813 has 2 divisors, whose sum is σ = 221021010019814. Its totient is φ = 221021010019812.

The previous prime is 221021010019783. The next prime is 221021010020059. The reversal of 221021010019813 is 318910010120122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 112035302516929 + 108985707502884 = 10584673^2 + 10439622^2 .

It is a cyclic number.

It is not a de Polignac number, because 221021010019813 - 2⁵ = 221021010019781 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221021010019013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110510505009906 + 110510505009907.

It is an arithmetic number, because the mean of its divisors is an integer number (110510505009907).

Almost surely, 2^{221021010019813} is an apocalyptic number.

It is an amenable number.

221021010019813 is a deficient number, since it is larger than the sum of its proper divisors (1).

221021010019813 is an equidigital number, since it uses as much as digits as its factorization.

221021010019813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 31.

Adding to 221021010019813 its reverse (318910010120122), we get a palindrome (539931020139935).

The spelling of 221021010019813 in words is "two hundred twenty-one trillion, twenty-one billion, ten million, nineteen thousand, eight hundred thirteen".