21121101221200 has 60 divisors (see below), whose sum is σ = 50744388170268. Its totient is φ = 8448283571200.

The previous prime is 21121101221189. The next prime is 21121101221267. The reversal of 21121101221200 is 212210112112.

It can be written as a sum of positive squares in 6 ways, for example, as 118275463744 + 21002825757456 = 343912^2 + 4582884^2 .

It is a super-2 number, since 2×21121101221200² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (16).

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, 22407420 + ... + 23330980.

Almost surely, 2^{21121101221200} is an apocalyptic number.

21121101221200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121101221200 is an abundant number, since it is smaller than the sum of its proper divisors (29623286949068).

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

21121101221200 is a wasteful number, since it uses less digits than its factorization.

21121101221200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 980752 (or 980741 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21121101221200 its reverse (212210112112), we get a palindrome (21333311333312).

The spelling of 21121101221200 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred one million, two hundred twenty-one thousand, two hundred".