21501443222021 has 8 divisors (see below), whose sum is σ = 24574936994880. Its totient is φ = 18428414205888.

The previous prime is 21501443221991. The next prime is 21501443222047. The reversal of 21501443222021 is 12022234410512.

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 21501443222021 - 2¹⁴ = 21501443205637 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 (21501443212021) 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, 116090036 + ... + 116275101.

It is an arithmetic number, because the mean of its divisors is an integer number (3071867124360).

Almost surely, 2^{21501443222021} is an apocalyptic number.

It is an amenable number.

21501443222021 is a deficient number, since it is larger than the sum of its proper divisors (3073493772859).

21501443222021 is a wasteful number, since it uses less digits than its factorization.

21501443222021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232378363.

The product of its (nonzero) digits is 7680, while the sum is 29.

Adding to 21501443222021 its reverse (12022234410512), we get a palindrome (33523677632533).

The spelling of 21501443222021 in words is "twenty-one trillion, five hundred one billion, four hundred forty-three million, two hundred twenty-two thousand, twenty-one".