21020011220121 has 8 divisors (see below), whose sum is σ = 28231255945824. Its totient is φ = 13911053653920.

The previous prime is 21020011220027. The next prime is 21020011220123. The reversal of 21020011220121 is 12102211002012.

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

It is not a de Polignac number, because 21020011220121 - 2¹⁹ = 21020010695833 is a prime.

It is a super-2 number, since 2×21020011220121² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21020011220121.

It is not an unprimeable number, because it can be changed into a prime (21020011220123) 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, 25571789395 + ... + 25571790216.

It is an arithmetic number, because the mean of its divisors is an integer number (3528906993228).

Almost surely, 2^{21020011220121} is an apocalyptic number.

It is an amenable number.

21020011220121 is a deficient number, since it is larger than the sum of its proper divisors (7211244725703).

21020011220121 is a wasteful number, since it uses less digits than its factorization.

21020011220121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51143579751.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21020011220121 its reverse (12102211002012), we get a palindrome (33122222222133).

The spelling of 21020011220121 in words is "twenty-one trillion, twenty billion, eleven million, two hundred twenty thousand, one hundred twenty-one".