220102210220021 has 4 divisors (see below), whose sum is σ = 220104934034700. Its totient is φ = 220099486405344.

The previous prime is 220102210219943. The next prime is 220102210220027. The reversal of 220102210220021 is 120022012201022.

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 182504293642225 + 37597916577796 = 13509415^2 + 6131714^2 .

It is a cyclic number.

It is not a de Polignac number, because 220102210220021 - 2²² = 220102206025717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220102210220027) 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, 1361786126 + ... + 1361947743.

It is an arithmetic number, because the mean of its divisors is an integer number (55026233508675).

Almost surely, 2^{220102210220021} is an apocalyptic number.

It is an amenable number.

220102210220021 is a deficient number, since it is larger than the sum of its proper divisors (2723814679).

220102210220021 is an equidigital number, since it uses as much as digits as its factorization.

220102210220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2723814678.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 220102210220021 its reverse (120022012201022), we get a palindrome (340124222421043).

The spelling of 220102210220021 in words is "two hundred twenty trillion, one hundred two billion, two hundred ten million, two hundred twenty thousand, twenty-one".