21120220020221 has 8 divisors (see below), whose sum is σ = 24698729060544. Its totient is φ = 17682044667840.

The previous prime is 21120220020161. The next prime is 21120220020257. The reversal of 21120220020221 is 12202002202112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-21120220020221 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21120220020221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120220020271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35083421660 + ... + 35083422261.

It is an arithmetic number, because the mean of its divisors is an integer number (3087341132568).

Almost surely, 2^{21120220020221} is an apocalyptic number.

It is an amenable number.

21120220020221 is a deficient number, since it is larger than the sum of its proper divisors (3578509040323).

21120220020221 is an equidigital number, since it uses as much as digits as its factorization.

21120220020221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70166843971.

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

Adding to 21120220020221 its reverse (12202002202112), we get a palindrome (33322222222333).

The spelling of 21120220020221 in words is "twenty-one trillion, one hundred twenty billion, two hundred twenty million, twenty thousand, two hundred twenty-one".