21111213031100 has 36 divisors (see below), whose sum is σ = 45811861863600. Its totient is φ = 8444387592960.

The previous prime is 21111213031093. The next prime is 21111213031141. The reversal of 21111213031100 is 113031211112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7805561 + ... + 10156239.

Almost surely, 2^{21111213031100} is an apocalyptic number.

21111213031100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21111213031100 is an abundant number, since it is smaller than the sum of its proper divisors (24700648832500).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21111213031100 is a wasteful number, since it uses less digits than its factorization.

21111213031100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2440502 (or 2440495 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 17.

Adding to 21111213031100 its reverse (113031211112), we get a palindrome (21224244242212).

The spelling of 21111213031100 in words is "twenty-one trillion, one hundred eleven billion, two hundred thirteen million, thirty-one thousand, one hundred".