21255201 has 24 divisors (see below), whose sum is σ = 34278816. Its totient is φ = 12579840.

The previous prime is 21255161. The next prime is 21255203. The reversal of 21255201 is 10255212.

It is not a de Polignac number, because 21255201 - 2⁹ = 21254689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21255203) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1761 + ... + 6753.

It is an arithmetic number, because the mean of its divisors is an integer number (1428284).

Almost surely, 2^21255201 is an apocalyptic number.

It is an amenable number.

21255201 is a deficient number, since it is larger than the sum of its proper divisors (13023615).

21255201 is a wasteful number, since it uses less digits than its factorization.

21255201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5053 (or 5050 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 21255201 is about 4610.3363217882. The cubic root of 21255201 is about 277.0055084552.

The spelling of 21255201 in words is "twenty-one million, two hundred fifty-five thousand, two hundred one".