21402240421211 has 16 divisors (see below), whose sum is σ = 23698370209248. Its totient is φ = 19200151872000.

The previous prime is 21402240421193. The next prime is 21402240421241. The reversal of 21402240421211 is 11212404220412.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21402240421211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21402240421241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24828965 + ... + 25676486.

It is an arithmetic number, because the mean of its divisors is an integer number (1481148138078).

Almost surely, 2^{21402240421211} is an apocalyptic number.

21402240421211 is a deficient number, since it is larger than the sum of its proper divisors (2296129788037).

21402240421211 is a wasteful number, since it uses less digits than its factorization.

21402240421211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50506382.

The product of its (nonzero) digits is 2048, while the sum is 26.

Adding to 21402240421211 its reverse (11212404220412), we get a palindrome (32614644641623).

The spelling of 21402240421211 in words is "twenty-one trillion, four hundred two billion, two hundred forty million, four hundred twenty-one thousand, two hundred eleven".