21111020201 has 8 divisors (see below), whose sum is σ = 21227692680. Its totient is φ = 20994631168.

The previous prime is 21111020197. The next prime is 21111020207. The reversal of 21111020201 is 10202011112.

It can be written as a sum of positive squares in 4 ways, for example, as 38142976 + 21072877225 = 6176^2 + 145165^2 .

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 21111020201 - 2² = 21111020197 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21111020207) 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, 79385 + ... + 220281.

It is an arithmetic number, because the mean of its divisors is an integer number (2653461585).

Almost surely, 2^21111020201 is an apocalyptic number.

It is an amenable number.

21111020201 is a deficient number, since it is larger than the sum of its proper divisors (116672479).

21111020201 is a wasteful number, since it uses less digits than its factorization.

21111020201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141723.

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

Adding to 21111020201 its reverse (10202011112), we get a palindrome (31313031313).

The spelling of 21111020201 in words is "twenty-one billion, one hundred eleven million, twenty thousand, two hundred one".