21223111201 has 4 divisors (see below), whose sum is σ = 21223967812. Its totient is φ = 21222254592.

The previous prime is 21223111153. The next prime is 21223111249. The reversal of 21223111201 is 10211132212.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21223111153) and next prime (21223111249).

It can be written as a sum of positive squares in 2 ways, for example, as 8902111201 + 12321000000 = 94351^2 + 111000^2 .

It is a cyclic number.

It is not a de Polignac number, because 21223111201 - 2¹¹ = 21223109153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21223111601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 390000 + ... + 441073.

It is an arithmetic number, because the mean of its divisors is an integer number (5305991953).

Almost surely, 2^21223111201 is an apocalyptic number.

It is an amenable number.

21223111201 is a deficient number, since it is larger than the sum of its proper divisors (856611).

21223111201 is an equidigital number, since it uses as much as digits as its factorization.

21223111201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 856610.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21223111201 its reverse (10211132212), we get a palindrome (31434243413).

The spelling of 21223111201 in words is "twenty-one billion, two hundred twenty-three million, one hundred eleven thousand, two hundred one".