21010211100 has 54 divisors (see below), whose sum is σ = 65855342280. Its totient is φ = 5602722720.

The previous prime is 21010211083. The next prime is 21010211137. The reversal of 21010211100 is 111201012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 11671440 + ... + 11673239.

Almost surely, 2^21010211100 is an apocalyptic number.

21010211100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21010211100 is an abundant number, since it is smaller than the sum of its proper divisors (44845131180).

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

21010211100 is a wasteful number, since it uses less digits than its factorization.

21010211100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23344699 (or 23344689 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 21010211100 its reverse (111201012), we get a palindrome (21121412112).

The spelling of 21010211100 in words is "twenty-one billion, ten million, two hundred eleven thousand, one hundred".