20211222021 has 8 divisors (see below), whose sum is σ = 28533489984. Its totient is φ = 12681551040.

The previous prime is 20211221999. The next prime is 20211222037. The reversal of 20211222021 is 12022211202.

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

It is not a de Polignac number, because 20211222021 - 2¹⁵ = 20211189253 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 (20211222091) 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, 198149185 + ... + 198149286.

It is an arithmetic number, because the mean of its divisors is an integer number (3566686248).

Almost surely, 2^20211222021 is an apocalyptic number.

It is an amenable number.

20211222021 is a deficient number, since it is larger than the sum of its proper divisors (8322267963).

20211222021 is a wasteful number, since it uses less digits than its factorization.

20211222021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396298491.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 20211222021 its reverse (12022211202), we get a palindrome (32233433223).

The spelling of 20211222021 in words is "twenty billion, two hundred eleven million, two hundred twenty-two thousand, twenty-one".