20001022001221 has 8 divisors (see below), whose sum is σ = 20870725892544. Its totient is φ = 19131325963200.

The previous prime is 20001022001209. The next prime is 20001022001287. The reversal of 20001022001221 is 12210022010002.

It is a happy number.

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 20001022001221 - 2²¹ = 20001019904069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20001022001321) 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, 3573310 + ... + 7264336.

It is an arithmetic number, because the mean of its divisors is an integer number (2608840736568).

Almost surely, 2^{20001022001221} is an apocalyptic number.

It is an amenable number.

20001022001221 is a deficient number, since it is larger than the sum of its proper divisors (869703891323).

20001022001221 is a wasteful number, since it uses less digits than its factorization.

20001022001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3926651.

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

Adding to 20001022001221 its reverse (12210022010002), we get a palindrome (32211044011223).

The spelling of 20001022001221 in words is "twenty trillion, one billion, twenty-two million, one thousand, two hundred twenty-one".