21225395 has 4 divisors (see below), whose sum is σ = 25470480. Its totient is φ = 16980312.

The previous prime is 21225353. The next prime is 21225397. The reversal of 21225395 is 59352212.

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

It is a cyclic number.

It is not a de Polignac number, because 21225395 - 2¹⁴ = 21209011 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21225397) 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, 2122535 + ... + 2122544.

It is an arithmetic number, because the mean of its divisors is an integer number (6367620).

Almost surely, 2^21225395 is an apocalyptic number.

21225395 is a deficient number, since it is larger than the sum of its proper divisors (4245085).

21225395 is an equidigital number, since it uses as much as digits as its factorization.

21225395 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4245084.

The product of its digits is 5400, while the sum is 29.

The square root of 21225395 is about 4607.1026687062. The cubic root of 21225395 is about 276.8759670079.

The spelling of 21225395 in words is "twenty-one million, two hundred twenty-five thousand, three hundred ninety-five".