2210100021 has 12 divisors (see below), whose sum is σ = 3278647372. Its totient is φ = 1433578176.

The previous prime is 2210100017. The next prime is 2210100031. The reversal of 2210100021 is 1200010122.

It can be written as a sum of positive squares in 2 ways, for example, as 2096357796 + 113742225 = 45786^2 + 10665^2 .

It is not a de Polignac number, because 2210100021 - 2² = 2210100017 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2210099976 and 2210100012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2210100031) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3318136 + ... + 3318801.

Almost surely, 2^2210100021 is an apocalyptic number.

It is an amenable number.

2210100021 is a deficient number, since it is larger than the sum of its proper divisors (1068547351).

2210100021 is a wasteful number, since it uses less digits than its factorization.

2210100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6636980 (or 6636977 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 2210100021 is about 47011.7008945645. The cubic root of 2210100021 is about 1302.5787119932.

Adding to 2210100021 its reverse (1200010122), we get a palindrome (3410110143).

The spelling of 2210100021 in words is "two billion, two hundred ten million, one hundred thousand, twenty-one".