21011021201121 has 8 divisors (see below), whose sum is σ = 32016794211264. Its totient is φ = 12006297829200.

The previous prime is 21011021201111. The next prime is 21011021201123. The reversal of 21011021201121 is 12110212011012.

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 21011021201121 - 2⁶ = 21011021201057 is a prime.

It is a super-2 number, since 2×21011021201121² (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 21011021201121.

It is not an unprimeable number, because it can be changed into a prime (21011021201123) 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, 500262409530 + ... + 500262409571.

It is an arithmetic number, because the mean of its divisors is an integer number (4002099276408).

Almost surely, 2^{21011021201121} is an apocalyptic number.

21011021201121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21011021201121 is a deficient number, since it is larger than the sum of its proper divisors (11005773010143).

21011021201121 is a wasteful number, since it uses less digits than its factorization.

21011021201121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1000524819111.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21011021201121 its reverse (12110212011012), we get a palindrome (33121233212133).

The spelling of 21011021201121 in words is "twenty-one trillion, eleven billion, twenty-one million, two hundred one thousand, one hundred twenty-one".