21000122011 has 8 divisors (see below), whose sum is σ = 22962382848. Its totient is φ = 19046721000.

The previous prime is 21000121997. The next prime is 21000122027. The reversal of 21000122011 is 11022100012.

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 21000122011 - 2⁵ = 21000121979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21000122041) 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, 2209995 + ... + 2219476.

It is an arithmetic number, because the mean of its divisors is an integer number (2870297856).

Almost surely, 2^21000122011 is an apocalyptic number.

21000122011 is a deficient number, since it is larger than the sum of its proper divisors (1962260837).

21000122011 is a wasteful number, since it uses less digits than its factorization.

21000122011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4429913.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21000122011 its reverse (11022100012), we get a palindrome (32022222023).

The spelling of 21000122011 in words is "twenty-one billion, one hundred twenty-two thousand, eleven".