20211001001221 has 8 divisors (see below), whose sum is σ = 20365389129888. Its totient is φ = 20056614474000.

The previous prime is 20211001001153. The next prime is 20211001001267. The reversal of 20211001001221 is 12210010011202.

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

It is a cyclic number.

It is not a de Polignac number, because 20211001001221 - 2¹⁷ = 20211000870149 is a prime.

It is a super-2 number, since 2×20211001001221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211001011221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42091431 + ... + 42568891.

It is an arithmetic number, because the mean of its divisors is an integer number (2545673641236).

Almost surely, 2^{20211001001221} is an apocalyptic number.

It is an amenable number.

20211001001221 is a deficient number, since it is larger than the sum of its proper divisors (154388128667).

20211001001221 is a wasteful number, since it uses less digits than its factorization.

20211001001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 800723.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 20211001001221 its reverse (12210010011202), we get a palindrome (32421011012423).

The spelling of 20211001001221 in words is "twenty trillion, two hundred eleven billion, one million, one thousand, two hundred twenty-one".