21012010122111 has 16 divisors (see below), whose sum is σ = 28040116664160. Its totient is φ = 13995955814400.

The previous prime is 21012010122107. The next prime is 21012010122137. The reversal of 21012010122111 is 11122101021012.

It is a happy number.

It is not a de Polignac number, because 21012010122111 - 2² = 21012010122107 is a prime.

It is a super-2 number, since 2×21012010122111² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012010122101) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 196774911 + ... + 196881663.

It is an arithmetic number, because the mean of its divisors is an integer number (1752507291510).

Almost surely, 2^{21012010122111} is an apocalyptic number.

21012010122111 is a deficient number, since it is larger than the sum of its proper divisors (7028106542049).

21012010122111 is a wasteful number, since it uses less digits than its factorization.

21012010122111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162586.

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

Adding to 21012010122111 its reverse (11122101021012), we get a palindrome (32134111143123).

The spelling of 21012010122111 in words is "twenty-one trillion, twelve billion, ten million, one hundred twenty-two thousand, one hundred eleven".