21654067 has 2 divisors, whose sum is σ = 21654068. Its totient is φ = 21654066.

The previous prime is 21654041. The next prime is 21654071. The reversal of 21654067 is 76045612.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21654067 - 2²³ = 13265459 is a prime.

It is not a weakly prime, because it can be changed into another prime (21654037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10827033 + 10827034.

It is an arithmetic number, because the mean of its divisors is an integer number (10827034).

Almost surely, 2^21654067 is an apocalyptic number.

21654067 is a deficient number, since it is larger than the sum of its proper divisors (1).

21654067 is an equidigital number, since it uses as much as digits as its factorization.

21654067 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 21654067 is about 4653.3930631315. The cubic root of 21654067 is about 278.7275037983.

Adding to 21654067 its reverse (76045612), we get a palindrome (97699679).

The spelling of 21654067 in words is "twenty-one million, six hundred fifty-four thousand, sixty-seven".