21001100212 has 24 divisors (see below), whose sum is σ = 38997189504. Its totient is φ = 9861693312.

The previous prime is 21001100179. The next prime is 21001100213. The reversal of 21001100212 is 21200110012.

It is a super-2 number, since 2×21001100212² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001100213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 298908 + ... + 362419.

It is an arithmetic number, because the mean of its divisors is an integer number (1624882896).

Almost surely, 2^21001100212 is an apocalyptic number.

It is an amenable number.

21001100212 is a deficient number, since it is larger than the sum of its proper divisors (17996089292).

21001100212 is a wasteful number, since it uses less digits than its factorization.

21001100212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661815 (or 661813 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21001100212 its reverse (21200110012), we get a palindrome (42201210224).

The spelling of 21001100212 in words is "twenty-one billion, one million, one hundred thousand, two hundred twelve".