21945067 has 2 divisors, whose sum is σ = 21945068. Its totient is φ = 21945066.

The previous prime is 21945043. The next prime is 21945073. The reversal of 21945067 is 76054912.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21945067 is a prime.

It is not a weakly prime, because it can be changed into another prime (21945017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10972533 + 10972534.

It is an arithmetic number, because the mean of its divisors is an integer number (10972534).

Almost surely, 2^21945067 is an apocalyptic number.

21945067 is a deficient number, since it is larger than the sum of its proper divisors (1).

21945067 is an equidigital number, since it uses as much as digits as its factorization.

21945067 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 21945067 is about 4684.5562223118. The cubic root of 21945067 is about 279.9705198554.

Adding to 21945067 its reverse (76054912), we get a palindrome (97999979).

The spelling of 21945067 in words is "twenty-one million, nine hundred forty-five thousand, sixty-seven".