21221001011 has 8 divisors (see below), whose sum is σ = 24266860800. Its totient is φ = 18178713288.

The previous prime is 21221001007. The next prime is 21221001017. The reversal of 21221001011 is 11010012212.

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

It is a cyclic number.

It is not a de Polignac number, because 21221001011 - 2² = 21221001007 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21221000983 and 21221001001.

It is not an unprimeable number, because it can be changed into a prime (21221001017) 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, 880271 + ... + 904056.

It is an arithmetic number, because the mean of its divisors is an integer number (3033357600).

Almost surely, 2^21221001011 is an apocalyptic number.

21221001011 is a deficient number, since it is larger than the sum of its proper divisors (3045859789).

21221001011 is a wasteful number, since it uses less digits than its factorization.

21221001011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1786033.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21221001011 its reverse (11010012212), we get a palindrome (32231013223).

The spelling of 21221001011 in words is "twenty-one billion, two hundred twenty-one million, one thousand, eleven".