21000011011 has 8 divisors (see below), whose sum is σ = 25043491584. Its totient is φ = 17217400200.

The previous prime is 21000010991. The next prime is 21000011027. The reversal of 21000011011 is 11011000012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21000011011 - 2⁷ = 21000010883 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (7).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21000010985 and 21000011003.

It is not an unprimeable number, because it can be changed into a prime (21000011051) 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, 65217265 + ... + 65217586.

It is an arithmetic number, because the mean of its divisors is an integer number (3130436448).

Almost surely, 2^21000011011 is an apocalyptic number.

21000011011 is a deficient number, since it is larger than the sum of its proper divisors (4043480573).

21000011011 is a wasteful number, since it uses less digits than its factorization.

21000011011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130434881.

The product of its (nonzero) digits is 2, while the sum is 7.

Adding to 21000011011 its reverse (11011000012), we get a palindrome (32011011023).

It can be divided in two parts, 2100001 and 1011, that added together give a palindrome (2101012).

The spelling of 21000011011 in words is "twenty-one billion, eleven thousand, eleven".