21011000211 has 32 divisors (see below), whose sum is σ = 31330880000. Its totient is φ = 13916077344.

The previous prime is 21011000209. The next prime is 21011000237. The reversal of 21011000211 is 11200011012.

It is a happy number.

It is not a de Polignac number, because 21011000211 - 2¹ = 21011000209 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21011000193 and 21011000202.

It is not an unprimeable number, because it can be changed into a prime (21011007211) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2662770 + ... + 2670648.

It is an arithmetic number, because the mean of its divisors is an integer number (979090000).

Almost surely, 2^21011000211 is an apocalyptic number.

21011000211 is a deficient number, since it is larger than the sum of its proper divisors (10319879789).

21011000211 is a wasteful number, since it uses less digits than its factorization.

21011000211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8520 (or 8514 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 21011000211 its reverse (11200011012), we get a palindrome (32211011223).

The spelling of 21011000211 in words is "twenty-one billion, eleven million, two hundred eleven", and thus it is an aban number.