21026201 has 4 divisors (see below), whose sum is σ = 24029952. Its totient is φ = 18022452.

The previous prime is 21026197. The next prime is 21026231. The reversal of 21026201 is 10262012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21026201 - 2² = 21026197 is a prime.

It is a super-2 number, since 2×21026201² = 884202256984802, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21026231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1501865 + ... + 1501878.

It is an arithmetic number, because the mean of its divisors is an integer number (6007488).

Almost surely, 2^21026201 is an apocalyptic number.

It is an amenable number.

21026201 is a deficient number, since it is larger than the sum of its proper divisors (3003751).

21026201 is an equidigital number, since it uses as much as digits as its factorization.

21026201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3003750.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 21026201 is about 4585.4335672867. The cubic root of 21026201 is about 276.0071105428.

Adding to 21026201 its reverse (10262012), we get a palindrome (31288213).

The spelling of 21026201 in words is "twenty-one million, twenty-six thousand, two hundred one".