21111001010031 has 32 divisors (see below), whose sum is σ = 28634232881088. Its totient is φ = 13831289763840.

The previous prime is 21111001010027. The next prime is 21111001010051. The reversal of 21111001010031 is 13001010011112.

It is not a de Polignac number, because 21111001010031 - 2² = 21111001010027 is a prime.

It is a super-2 number, since 2×21111001010031² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21111001009989 and 21111001010016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111001010051) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1432509495 + ... + 1432524231.

It is an arithmetic number, because the mean of its divisors is an integer number (894819777534).

Almost surely, 2^{21111001010031} is an apocalyptic number.

21111001010031 is a deficient number, since it is larger than the sum of its proper divisors (7523231871057).

21111001010031 is a wasteful number, since it uses less digits than its factorization.

21111001010031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21051.

The product of its (nonzero) digits is 6, while the sum is 12.

Adding to 21111001010031 its reverse (13001010011112), we get a palindrome (34112011021143).

The spelling of 21111001010031 in words is "twenty-one trillion, one hundred eleven billion, one million, ten thousand, thirty-one".