221002022110021 has 4 divisors (see below), whose sum is σ = 221038972796844. Its totient is φ = 220965071423200.

The previous prime is 221002022109949. The next prime is 221002022110039. The reversal of 221002022110021 is 120011220200122.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2866550361921 + 218135471748100 = 1693089^2 + 14769410^2 .

It is a cyclic number.

It is not a de Polignac number, because 221002022110021 - 2⁹ = 221002022109509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221002022109977 and 221002022110004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221002062110021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18475334440 + ... + 18475346401.

It is an arithmetic number, because the mean of its divisors is an integer number (55259743199211).

Almost surely, 2^{221002022110021} is an apocalyptic number.

It is an amenable number.

221002022110021 is a deficient number, since it is larger than the sum of its proper divisors (36950686823).

221002022110021 is an equidigital number, since it uses as much as digits as its factorization.

221002022110021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36950686822.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 221002022110021 its reverse (120011220200122), we get a palindrome (341013242310143).

The spelling of 221002022110021 in words is "two hundred twenty-one trillion, two billion, twenty-two million, one hundred ten thousand, twenty-one".