21055201 has 4 divisors (see below), whose sum is σ = 21503232. Its totient is φ = 20607172.

The previous prime is 21055147. The next prime is 21055207. The reversal of 21055201 is 10255012.

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 a cyclic number.

It is not a de Polignac number, because 21055201 - 2²³ = 12666593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21055207) 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, 223945 + ... + 224038.

It is an arithmetic number, because the mean of its divisors is an integer number (5375808).

Almost surely, 2^21055201 is an apocalyptic number.

It is an amenable number.

21055201 is a deficient number, since it is larger than the sum of its proper divisors (448031).

21055201 is an equidigital number, since it uses as much as digits as its factorization.

21055201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 448030.

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 21055201 is about 4588.5946650363. The cubic root of 21055201 is about 276.1339448219.

The spelling of 21055201 in words is "twenty-one million, fifty-five thousand, two hundred one".