21380467 has 2 divisors, whose sum is σ = 21380468. Its totient is φ = 21380466.

The previous prime is 21380423. The next prime is 21380473. The reversal of 21380467 is 76408312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21380467 - 2¹¹ = 21378419 is a prime.

It is not a weakly prime, because it can be changed into another prime (21380267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10690233 + 10690234.

It is an arithmetic number, because the mean of its divisors is an integer number (10690234).

Almost surely, 2^21380467 is an apocalyptic number.

21380467 is a deficient number, since it is larger than the sum of its proper divisors (1).

21380467 is an equidigital number, since it uses as much as digits as its factorization.

21380467 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 21380467 is about 4623.9017074328. The cubic root of 21380467 is about 277.5486136188.

Adding to 21380467 its reverse (76408312), we get a palindrome (97788779).

The spelling of 21380467 in words is "twenty-one million, three hundred eighty thousand, four hundred sixty-seven".