20111020021 has 8 divisors (see below), whose sum is σ = 21247153920. Its totient is φ = 19004396208.

The previous prime is 20111020019. The next prime is 20111020031. The reversal of 20111020021 is 12002011102.

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 20111020021 - 2¹ = 20111020019 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20111020031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7376121 + ... + 7378846.

It is an arithmetic number, because the mean of its divisors is an integer number (2655894240).

Almost surely, 2^20111020021 is an apocalyptic number.

It is an amenable number.

20111020021 is a deficient number, since it is larger than the sum of its proper divisors (1136133899).

20111020021 is a wasteful number, since it uses less digits than its factorization.

20111020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14755043.

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

Adding to 20111020021 its reverse (12002011102), we get a palindrome (32113031123).

The spelling of 20111020021 in words is "twenty billion, one hundred eleven million, twenty thousand, twenty-one".