21211122110100 has 288 divisors, whose sum is σ = 73662559044480. Its totient is φ = 4655434383360.

The previous prime is 21211122110077. The next prime is 21211122110137. The reversal of 21211122110100 is 101122111212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21211122110100.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 7159417 + ... + 9678816.

It is an arithmetic number, because the mean of its divisors is an integer number (255772774460).

Almost surely, 2^{21211122110100} is an apocalyptic number.

21211122110100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211122110100 is an abundant number, since it is smaller than the sum of its proper divisors (52451436934380).

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

21211122110100 is a wasteful number, since it uses less digits than its factorization.

21211122110100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16838299 (or 16838292 counting only the distinct ones).

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

Adding to 21211122110100 its reverse (101122111212), we get a palindrome (21312244221312).

The spelling of 21211122110100 in words is "twenty-one trillion, two hundred eleven billion, one hundred twenty-two million, one hundred ten thousand, one hundred".