21452271 has 4 divisors (see below), whose sum is σ = 28603032. Its totient is φ = 14301512.

The previous prime is 21452269. The next prime is 21452309. The reversal of 21452271 is 17225412.

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 21452271 - 2¹ = 21452269 is a prime.

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21452201) 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, 3575376 + ... + 3575381.

It is an arithmetic number, because the mean of its divisors is an integer number (7150758).

Almost surely, 2^21452271 is an apocalyptic number.

21452271 is a deficient number, since it is larger than the sum of its proper divisors (7150761).

21452271 is an equidigital number, since it uses as much as digits as its factorization.

21452271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7150760.

The product of its digits is 1120, while the sum is 24.

The square root of 21452271 is about 4631.6596377541. The cubic root of 21452271 is about 277.8589721698.

Adding to 21452271 its reverse (17225412), we get a palindrome (38677683).

The spelling of 21452271 in words is "twenty-one million, four hundred fifty-two thousand, two hundred seventy-one".