21443020121 has 8 divisors (see below), whose sum is σ = 21858530400. Its totient is φ = 21029245600.

The previous prime is 21443020069. The next prime is 21443020127. The reversal of 21443020121 is 12102034412.

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 21443020121 - 2³⁴ = 4263150937 is a prime.

It is a super-2 number, since 2×21443020121² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21443020093 and 21443020102.

It is not an unprimeable number, because it can be changed into a prime (21443020127) 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, 408980 + ... + 458421.

It is an arithmetic number, because the mean of its divisors is an integer number (2732316300).

Almost surely, 2^21443020121 is an apocalyptic number.

It is an amenable number.

21443020121 is a deficient number, since it is larger than the sum of its proper divisors (415510279).

21443020121 is an equidigital number, since it uses as much as digits as its factorization.

21443020121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 867879.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21443020121 its reverse (12102034412), we get a palindrome (33545054533).

The spelling of 21443020121 in words is "twenty-one billion, four hundred forty-three million, twenty thousand, one hundred twenty-one".