21121222012100 has 72 divisors (see below), whose sum is σ = 52462094586048. Its totient is φ = 7230299529600.

The previous prime is 21121222012091. The next prime is 21121222012103. The reversal of 21121222012100 is 121022212112.

It is a super-2 number, since 2×21121222012100² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21121222012103) 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, 23012711 + ... + 23912910.

It is an arithmetic number, because the mean of its divisors is an integer number (728640202584).

Almost surely, 2^{21121222012100} is an apocalyptic number.

21121222012100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121222012100 is an abundant number, since it is smaller than the sum of its proper divisors (31340872573948).

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

21121222012100 is a wasteful number, since it uses less digits than its factorization.

21121222012100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46926285 (or 46926278 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21121222012100 its reverse (121022212112), we get a palindrome (21242244224212).

The spelling of 21121222012100 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred twenty-two million, twelve thousand, one hundred".