21221011121000 has 64 divisors (see below), whose sum is σ = 50148821370960. Its totient is φ = 8404360800000.

The previous prime is 21221011120979. The next prime is 21221011121081. The reversal of 21221011121000 is 12111012212.

It can be written as a sum of positive squares in 8 ways, for example, as 9944726232676 + 11276284888324 = 3153526^2 + 3358018^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 104953511 + ... + 105155510.

Almost surely, 2^{21221011121000} is an apocalyptic number.

21221011121000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221011121000 is an abundant number, since it is smaller than the sum of its proper divisors (28927810249960).

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

21221011121000 is a wasteful number, since it uses less digits than its factorization.

21221011121000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210109143 (or 210109129 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21221011121000 its reverse (12111012212), we get a palindrome (21233122133212).

The spelling of 21221011121000 in words is "twenty-one trillion, two hundred twenty-one billion, eleven million, one hundred twenty-one thousand".