21002212122111 has 48 divisors (see below), whose sum is σ = 33359222108160. Its totient is φ = 12626782277760.

The previous prime is 21002212122061. The next prime is 21002212122121. The reversal of 21002212122111 is 11122121220012.

21002212122111 is a `hidden beast` number, since 21 + 0 + 0 + 221 + 212 + 211 + 1 = 666.

It is not a de Polignac number, because 21002212122111 - 2³⁷ = 20864773168639 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002212122121) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 102732451 + ... + 102936683.

It is an arithmetic number, because the mean of its divisors is an integer number (694983793920).

Almost surely, 2^{21002212122111} is an apocalyptic number.

21002212122111 is a deficient number, since it is larger than the sum of its proper divisors (12357009986049).

21002212122111 is a wasteful number, since it uses less digits than its factorization.

21002212122111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212556 (or 212553 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21002212122111 its reverse (11122121220012), we get a palindrome (32124333342123).

The spelling of 21002212122111 in words is "twenty-one trillion, two billion, two hundred twelve million, one hundred twenty-two thousand, one hundred eleven".