21527867 has 2 divisors, whose sum is σ = 21527868. Its totient is φ = 21527866.

The previous prime is 21527851. The next prime is 21527873. The reversal of 21527867 is 76872512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21527867 - 2⁴ = 21527851 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21527867.

It is not a weakly prime, because it can be changed into another prime (21527887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10763933 + 10763934.

It is an arithmetic number, because the mean of its divisors is an integer number (10763934).

Almost surely, 2^21527867 is an apocalyptic number.

21527867 is a deficient number, since it is larger than the sum of its proper divisors (1).

21527867 is an equidigital number, since it uses as much as digits as its factorization.

21527867 is an evil number, because the sum of its binary digits is even.

The product of its digits is 47040, while the sum is 38.

The square root of 21527867 is about 4639.8132505522. The cubic root of 21527867 is about 278.1849734237.

It can be divided in two parts, 215 and 27867, that added together give a palindrome (28082).

The spelling of 21527867 in words is "twenty-one million, five hundred twenty-seven thousand, eight hundred sixty-seven".