102210100021 has 4 divisors (see below), whose sum is σ = 102288664044. Its totient is φ = 102131536000.

The previous prime is 102210100019. The next prime is 102210100067. The reversal of 102210100021 is 120001012201.

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 6984780625 + 95225319396 = 83575^2 + 308586^2 .

It is a cyclic number.

It is not a de Polignac number, because 102210100021 - 2¹ = 102210100019 is a prime.

It is a super-3 number, since 3×102210100021³ (a number of 34 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 102210099980 and 102210100007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102210100721) 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, 39280060 + ... + 39282661.

It is an arithmetic number, because the mean of its divisors is an integer number (25572166011).

Almost surely, 2^102210100021 is an apocalyptic number.

It is an amenable number.

102210100021 is a deficient number, since it is larger than the sum of its proper divisors (78564023).

102210100021 is an equidigital number, since it uses as much as digits as its factorization.

102210100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78564022.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 102210100021 its reverse (120001012201), we get a palindrome (222211112222).

The spelling of 102210100021 in words is "one hundred two billion, two hundred ten million, one hundred thousand, twenty-one".