21111011012100 has 72 divisors (see below), whose sum is σ = 61256209907200. Its totient is φ = 5613472241280.

The previous prime is 21111011012089. The next prime is 21111011012107. The reversal of 21111011012100 is 121011011112.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (21111011012107) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 100711972 + ... + 100921371.

Almost surely, 2^{21111011012100} is an apocalyptic number.

21111011012100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21111011012100 is an abundant number, since it is smaller than the sum of its proper divisors (40145198895100).

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

21111011012100 is a wasteful number, since it uses less digits than its factorization.

21111011012100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201633709 (or 201633702 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 12.

Adding to 21111011012100 its reverse (121011011112), we get a palindrome (21232022023212).

It can be divided in two parts, 21111011012 and 100, that added together give a palindrome (21111011112).

The spelling of 21111011012100 in words is "twenty-one trillion, one hundred eleven billion, eleven million, twelve thousand, one hundred".