21020221201 has 4 divisors (see below), whose sum is σ = 24023109952. Its totient is φ = 18017332452.

The previous prime is 21020221153. The next prime is 21020221259. The reversal of 21020221201 is 10212202012.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21020221201 - 2⁷ = 21020221073 is a prime.

It is a super-3 number, since 3×21020221201³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21020221501) 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, 1501444365 + ... + 1501444378.

It is an arithmetic number, because the mean of its divisors is an integer number (6005777488).

Almost surely, 2^21020221201 is an apocalyptic number.

It is an amenable number.

21020221201 is a deficient number, since it is larger than the sum of its proper divisors (3002888751).

21020221201 is an equidigital number, since it uses as much as digits as its factorization.

21020221201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3002888750.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21020221201 its reverse (10212202012), we get a palindrome (31232423213).

The spelling of 21020221201 in words is "twenty-one billion, twenty million, two hundred twenty-one thousand, two hundred one".