21211121002000 has 40 divisors (see below), whose sum is σ = 51288490587672. Its totient is φ = 8484448400000.

The previous prime is 21211121001977. The next prime is 21211121002007. The reversal of 21211121002000 is 20012111212.

It can be written as a sum of positive squares in 4 ways, for example, as 46557555984 + 21164563446016 = 215772^2 + 4600496^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×21211121002000² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21211121002007) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5302778251 + ... + 5302782250.

Almost surely, 2^{21211121002000} is an apocalyptic number.

21211121002000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211121002000 is an abundant number, since it is smaller than the sum of its proper divisors (30077369585672).

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

21211121002000 is a wasteful number, since it uses less digits than its factorization.

21211121002000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10605560524 (or 10605560508 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21211121002000 its reverse (20012111212), we get a palindrome (21231133113212).

The spelling of 21211121002000 in words is "twenty-one trillion, two hundred eleven billion, one hundred twenty-one million, two thousand".