21452567 has 2 divisors, whose sum is σ = 21452568. Its totient is φ = 21452566.

The previous prime is 21452549. The next prime is 21452569. The reversal of 21452567 is 76525412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21452567 - 2⁶ = 21452503 is a prime.

Together with 21452569, it forms a pair of twin primes.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is equal to p_1356773 and since 21452567 and 1356773 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21452569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10726283 + 10726284.

It is an arithmetic number, because the mean of its divisors is an integer number (10726284).

Almost surely, 2^21452567 is an apocalyptic number.

21452567 is a deficient number, since it is larger than the sum of its proper divisors (1).

21452567 is an equidigital number, since it uses as much as digits as its factorization.

21452567 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16800, while the sum is 32.

The square root of 21452567 is about 4631.6915916326. The cubic root of 21452567 is about 277.8602501367.

Adding to 21452567 its reverse (76525412), we get a palindrome (97977979).

The spelling of 21452567 in words is "twenty-one million, four hundred fifty-two thousand, five hundred sixty-seven".