21020221011 has 8 divisors (see below), whose sum is σ = 28049623504. Its totient is φ = 14002149600.

The previous prime is 21020220967. The next prime is 21020221031. The reversal of 21020221011 is 11012202012.

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

It is not a de Polignac number, because 21020221011 - 2⁷ = 21020220883 is a prime.

It is a super-3 number, since 3×21020221011³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21020221031) 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, 2828440 + ... + 2835861.

It is an arithmetic number, because the mean of its divisors is an integer number (3506202938).

Almost surely, 2^21020221011 is an apocalyptic number.

21020221011 is a deficient number, since it is larger than the sum of its proper divisors (7029402493).

21020221011 is a wasteful number, since it uses less digits than its factorization.

21020221011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5665541.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21020221011 its reverse (11012202012), we get a palindrome (32032423023).

The spelling of 21020221011 in words is "twenty-one billion, twenty million, two hundred twenty-one thousand, eleven".