20023221021 has 8 divisors (see below), whose sum is σ = 27858394560. Its totient is φ = 12768430752.

The previous prime is 20023221017. The next prime is 20023221073. The reversal of 20023221021 is 12012232002.

It is a happy number.

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

It is not a de Polignac number, because 20023221021 - 2² = 20023221017 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20023221011) 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, 145095736 + ... + 145095873.

It is an arithmetic number, because the mean of its divisors is an integer number (3482299320).

Almost surely, 2^20023221021 is an apocalyptic number.

It is an amenable number.

20023221021 is a deficient number, since it is larger than the sum of its proper divisors (7835173539).

20023221021 is a wasteful number, since it uses less digits than its factorization.

20023221021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 290191635.

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 20023221021 its reverse (12012232002), we get a palindrome (32035453023).

The spelling of 20023221021 in words is "twenty billion, twenty-three million, two hundred twenty-one thousand, twenty-one".