20021001211 has 4 divisors (see below), whose sum is σ = 20028061152. Its totient is φ = 20013941272.

The previous prime is 20021001193. The next prime is 20021001229. The reversal of 20021001211 is 11210012002.

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

It is an interprime number because it is at equal distance from previous prime (20021001193) and next prime (20021001229).

It is a cyclic number.

It is not a de Polignac number, because 20021001211 - 2²⁵ = 19987446779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20021001311) 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, 3525715 + ... + 3531388.

It is an arithmetic number, because the mean of its divisors is an integer number (5007015288).

Almost surely, 2^20021001211 is an apocalyptic number.

20021001211 is a deficient number, since it is larger than the sum of its proper divisors (7059941).

20021001211 is an equidigital number, since it uses as much as digits as its factorization.

20021001211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7059940.

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

Adding to 20021001211 its reverse (11210012002), we get a palindrome (31231013213).

The spelling of 20021001211 in words is "twenty billion, twenty-one million, one thousand, two hundred eleven".